Kind: captions
Language: en
let me ask you to this
question whether it's bell curve or any
research on
race differences
can that be used to increase the amount
of racism in the world can that be used
to increase the amount of hate in the
world
my sense is
there is such
enormous
reservoirs of hate and racism
that have nothing to do with scientific
knowledge of the data
that speak against that
that
no i don't
i don't want to give racist groups of
veto power over what scientists study
the following is a conversation with
richard heyer on the science of human
intelligence this is a highly
controversial topic but a critically
important one for understanding the
human mind
i hope you will join me in not shying
away from difficult topics like this
and instead
let us try to navigate it with empathy
rigor and grace
if you're watching this on video now i
should mention that i'm recording this
introduction
in an undisclosed location somewhere in
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in the description and now dear friends
here's richard higher
what are the measures of human
intelligence and how do we measure it
everybody has an idea of what they mean
by intelligence
in the in the vernacular what i mean by
intelligence is just being smart how
well you reason how well you figure
things out what you do when you don't
know what to do
those are just
kind of everyday common sense
definitions of how people use the word
intelligence if you want to do research
on intelligence
measuring something that you can study
scientifically is a little trickier
and what almost all researchers who
study intelligence use
is the concept called the g factor
general intelligence
and that is what is common that is a
mental ability that is common to
virtually all tests
of mental abilities what's the origin of
the term g factor by the way it's such a
funny word for such a fundamental human
thing the general factor i really
started with charles spearman
and he noticed this is like a boy more
than a hundred years ago
uh he noticed
that
when you tested people with different
tests
all the tests were correlated positively
and so he was looking at student exams
and things
and he invented the correlation
coefficient essentially
and he
when he used it to look at student
performance on various topics he found
they all the scores were correlated with
each other and they were all positive
correlations so he inferred from this
that there must be some common factor
that was irrespective of the content of
the test and positive correlation means
if you do well on on the first test
you're likely to do well in the second
test and presumably that holds
for tests across even disciplines so
not within subject but across subjects
so that's
where the general comes in some
something about general intelligence so
when you were talking about measuring
intelligence and and trying to figure
out
something difficult about this world and
how to solve the puzzles of this world
that means generally speaking not some
specific tests but across all tests
absolutely right and people get hung up
on this
uh because they said well what about the
ability to do x
isn't that
independent and they said i know
somebody who's very good at this but not
so good at this other thing yeah and so
there are a lot of examples like that
but it's a general tendency so
exceptions really don't disprove
you know your your everyday experience
is not the same as what the data
actually
show and your everyday experience when
you say oh i know someone who's good at
x but not so good at why that doesn't
contradict the statement of about a he's
not so good but he's not the opposite
he's not a it's not a negative
correlation
okay so we're not with our anecdotal
data
i know a guy is really good at
solving some kind of visual thing
that's not
sufficient for us to understand actually
the depths of that person's intelligence
so
how this idea of g factor
how much evidence is there
how strong
you know given across the decades that
this idea has been around how much has
it been held up that there is a
universal
uh
sort of horsepower of intelligence
that's underneath all of it all the
different tests we do to try to get to
this thing
uh in in the depths of the human mind
that's a that's a universal stable
measure of a person's intelligence
you used a couple of words in there yeah
stable and
we have to be precise with words well
hoping we can get away with being poetic
we can there's a lot about research in
general not just intelligence research
that is poetic
science has a phonetic aspect to it and
good scientists are are very intuitive
they're not just
hey these are the numbers you have to
kind of step back and see the big
picture when it comes to
intelligence
research you asked how well has this
general concept held up and i think i
can say
without fear of being empirically
contradicted
that it is the most replicated finding
in all of psychology
now some cynics may say well big deal
psychology we all know there's a
replication crisis in psychology and a
lot of this stuff doesn't replicate
that's all true there is no replication
crisis when it comes to studying the the
existence of this general factor let me
tell you some things about it it is it
it looks like it's universal in uh that
you find it in all cultures
the way you find it let's step back one
one step the way you find it is to give
a battery of mental tests
what battery you choose take a battery
of any mental test you want
give it to a large number of diverse
people
and you will be able to extract
statistically
the comment the commonality among all
those tests it's done by a technique
called factor analysis you
people
uh
think that's that this may be a
statistical artifact of some kind it is
not a statistical artifact
what is factor analysis factor analysis
is a way of looking at a big set of data
and look at the correlation among the
different test scores and then find
empirically the clusters of scores that
go together
and there are different factors so if
you have a bunch of mental tests there
may be a verbal factor there may be a
numerical factor there may be a visual
spatial factor but those factors have
variants in common with each other and
that is the common
uh that's what's common among all the
tests and that's what gets labeled the g
factor so if you give a diverse battery
of mental tests
and you extract a g factor from it that
factor usually accounts for around half
of the variance it's the single biggest
factor but it's not the only factor
but it is the most reliable it is the
most stable
and it seems
to be very much influenced by genetics
it's very hard to change the g factor
with training
or
drugs
or anything else don't know how to
increase the g factor okay you said a
lot of really interesting things there
so
first i mean just to get people used to
in case they're not familiar with this
idea g factor
is what we mean so often there's a uh
this term used iq
which is
the way i iq is used they really mean g
factor
in regular conversation
the way cause we what we mean by iq we
mean intelligence and what we mean by
intelligence we mean general
intelligence and general intelligence in
the human mind
from a psychology from a serious
rigorous scientific perspective actually
means g factor so g factor equals
intelligence just in this conversation
to define terms okay so so there's this
stable thing called g factor you said
now
factor you said factor many times
means
a measure
that's a potential could be reduced to a
single number across the different
factors you mentioned
and
uh
what you said it accounts for half
half ish
accounts for half ish of what of
variance across the different
set of tests
so if you're if you do for some reason
well on some set of tests
what does that mean so that that means
there's some unique capabilities outside
of the g factor that might account for
that and what are those
what else is there besides the raw
horsepower the engine inside your mind
that generates intelligence there are
test taking skills
there are specific abilities
someone might be particularly good
uh
at
mathematical things mathematical
concepts even simple arithmetic people
are some people are much better than
others you might know people who can
memorize and short-term memory is
another uh
component of this
uh short-term memory is one of the
cognitive processes that's most highly
correlated with the g factor
so
so all those things like memory uh taste
test taking skills account for
variability across the the test
performances but you so you can
you can run but you can't hide
from the thing that god gave you the
genetics
so that g factor
science says that g factor is there each
one of us have
each one of us has a g factor oh boy
some have more than others i'm getting
uncomfortable already well iq is a score
and i q an iq score is a very good
estimate of the g factor you can't
measure g directly there's no direct
measure you estimate it from these
statistical techniques
but an iq score is a good estimate why
because a standard iq test is a battery
of different mental abilities
you combined it into one score
and that score is highly correlated with
the g factor even if you get better
scores on some subtest than others
because again it's what's common to all
these mental abilities so that a good iq
test
and i'll ask you about that but a good
iq test tries to compress down
that battery of tests like tries to get
a nice battery
the nice selection of variable tests
into one test
and so in that way it sneaks up to this
gfa and that's another interesting thing
about g factor
now you give first of all you have a
great book
on the neuroscience of intelligence you
have a great course which is when i
first learned
you're a great teacher let me just thank
you
uh you
your course at the teaching company i
hope i'm saying that correctly the
intelligent brain the intelligent brain
is when i first
heard about this g factor this
mysterious thing that lurks in the
darkness that we cannot quite shine at
light on we're trying to sneak up on
so the fact that there's this measure
stable measure of intelligence we can't
measure directly
but we can come up with a battery test
or one test that includes a battery of
um
variable type of
questions that can
reliably or
attempt to estimate in a stable way that
g factor that's a fascinating idea so
for me as an ai person it's fascinating
it's fascinating there's something
stable like that about the human mind
especially if it's grounded in genetics
it's both fascinating
that
as a researcher of the human mind
and
all the human
[Music]
psychological sociological ethical
questions that start arising it makes me
uncomfortable but truth can be
uncomfortable
you know i i get that a lot about being
uncomfortable talking about this
uh let me go back and just say one more
empirical thing
uh it doesn't matter
which battery of tests you use
so there are countless tests you can
take any 12 of them at random
extract a g factor and another 12 at
random and extracted g factor and those
g factors will be highly correlated like
over 0.9 with each other that's very so
it is a ubiquitous it doesn't depend on
the content of the test is what i'm
trying to say yes it is general among
all those tests of mental ability and
tests of mental you know mental
abilities include things like geez uh
playing poker
your skill at poker is not unrelated to
g
your skill at anything that requires
reasoning and thinking anything from
spelling
arithmetic
more complex things
uh this concept is ubiquitous and when
you do batteries of tests in different
cultures you get the same thing
so this says something interesting about
the human mind that is a computer is
designed to be
general
so that means you can
[Music]
so it's not
it's not easily made specialized
meaning
if you're going to be good at one thing
miyamoto musashi has this
quote he's an ancient warrior uh famous
for the book of five rings in the
martial arts world and
the quote goes if you know the way
broadly you will see it in everything
meaning if you
do
one thing is going to generalize
to everything
and that that's an interesting thing
about the human mind
so that that's what the g factor
reveals okay
so what's the difference if you can
elaborate a little bit further between
iq and g factor just because it's a
source of confusion for people and iq is
is a score people use the word iq to
mean intelligence but iq has a more
technical meaning
for people who work in the field and i
it's an iq score score on a test that
estimates the g factor
and the g factor is what's common among
all these tests of mental ability so if
you think about it's not a venn diagram
but um i guess you could make a venn
diagram out of it but the g factor would
be really at the core
what's what's common to everything
and i what iq scores do is they allow a
rank order of people on the score
and this is what makes people
uncomfortable this is where there's a
lot of controversy about whether iq
tests are biased toward any one group or
another
and
a lot of the the answers to these
questions are very clear but they also
have a technical aspect of it that's not
so easy to to explain well we'll talk
about the fascinating and the difficult
things about all of this but uh
so by the way when you say rank order
that means you get a number and that
means one person you can now compare
like uh
you could say that this other person is
more intelligent than me
well what you can say is
iq scores are interpreted really as
percentiles
so that
uh if you have an iq of 140 and somebody
else has 70 the metric is such that you
cannot say the person with an iq of 140
is twice as smart
as a person with an iq of
that would require a ratio scale with an
absolute zero now you may think you know
people with zero intelligence but in
fact there is no absolute zero on on an
iq scale it's relative to other people
so relative to other people somebody
with an iq score of 140 is in the upper
less than one percent
whereas
somebody with an iq of 70 is two
standard deviations below the mean that
that's that's a different percentile so
it's similar to like in chess you have
an elo rating that's designed to
rank order
people
uh so you can't say it's twice
one person if if your yield rating is
twice
another person i don't think you're
twice as good at chess
it's not stable in that way but because
it's very difficult to do these kinds of
comparisons
but uh
so what can we say about the number
itself
is that stable
across tests and so on or no there are a
number of statistical properties of any
test they're called psychometric
properties you have validity you have
reliability
reliability there are many different
kinds of reliability they all
essentially measure stability
and iq tests are stable within an
individual there are some longitudinal
studies where
children were measured at age 11 and
again when they were 70 years old and
the two iq scores are highly correlated
with each other this comes from a
fascinating study from
scotland
uh in the 1930s some researchers decided
to get an iq test on every single child
age 11 in the whole country
and they did
and
those records
were discovered in an old storeroom at
the university of edinburgh
by a friend of mine ian deary who
found the records
digitized them and has done a lot of
research on
the people who are still alive today
from that original study including brain
imaging research by the way really it's
a fascinating group of
of people who are who were studied
not to get ahead of the story but one of
the most interesting things they found
is a very strong relationship between iq
measured at age 11
and mortality
so that
you know
in the
70 years later
they looked at the survival rates and
they could get death records from
everybody and scotland has universal
health care for everybody
and it turned out if you divide
people by their age 11 iq score into
quartiles
and then look at how many people are
alive
70 years later
the
i know this is in the book they have the
graph in the book
but there are essentially twice as many
people alive in the highest iq quartile
than in the lowest iq quartile it's true
in men and women
um interesting
so it makes a big difference now why
this is the case
is not so clear
since everyone had access to health care
well there's a lot and we'll talk about
it you know
just
the sentences you used now
could be explained by
nature or nurture we don't know now
there's a lot of science that starts to
then dig in and investigate that
question but let me linger on the iq
test how are the tests designed iq tests
designed how do they work maybe some
examples for people who are not aware
what
what makes a good iq test question that
sneaks up on this on this g factor
measure well your question is
interesting because you want me to give
examples of items that make good items
and what makes a good item is not so
much its content
but its empirical relationship to the
total score that
turns out to be valid by other means
yeah so for example
let me give you an odd example from
personality testing nice
so there's a personality test called the
minnesota multiphasic personality
inventory mmpi been around for decades
i've heard about this test recently
because of the johnny depp and uh amber
heard trial i don't know if you've been
paying attention to that but they have
not been paying attention they had
psychologists on the st on the stand and
they were talking apparently those
psychologists did uh again i'm learning
so much from this trial they have uh
they did different at the battery of
tests
to uh diagnose personality disorders
apparently there's that
systematic way of doing so and the
minnesota one is
one of the ones that there's the most
science on there's a lot of great papers
which were all
continuously cited on the stand which is
fascinating to watch sorry a little bit
of attention okay i mean this is
interesting because you're right it's
been around for decades there's a lot of
scientific research on the psychometric
properties
of the test including what it predicts
with respect to different categories of
personality disorder but what i want to
mention is the content of the items on
that test
all of the items
are essentially
true false items
true or false i prefer a shower to a
bath
true or false
i think lincoln was a better president
than washington
what have all these what does that have
to do
and the point is the content of these
items nobody knows why
these items in aggregate predict
anything but empirically they do
it's a technique of of choosing items
for a test
that is called dust bowl empiricism
that the content doesn't matter but
there it for some reason when you get a
criterion group of people with this
disorder and you compare them to people
without that disorder these are the
items that distinguish
irrespective of content it's a hard
concept to grasp well uh first of all
it's fascinating
but
uh from uh because i
i i consider myself part psychologist
because i love human robot interaction
and that's a problem half of that
problem
is a psychology problem because there's
a human
so designing these tests to get at the
questions is the fascinating part like
how do you get
to uh like what does dust bowl
empiricism refer to does it
refer to the final result
yeah so it's the test is dust bowl
empiricism but how do you arrive at the
battery of questions i presume
uh one of the things now again i'm going
to the excellent testimony in that trial
the explanation also they explain the
tests
uh
that a bunch of the questions are kind
of
make you
forget that you're taking a test
like
it makes it very difficult for you to
somehow figure out what what uh
you're supposed to answer yes it's
called social desirability but we're
getting a little far afield because i
only wanted to give that example of dust
bowl empiricism
when we talk about the items on an iq
test
many of those
items in the dust bowl and piercing
method have no face validity in other
words they don't look like they measure
anything
yes
whereas most intelligence tests the
items actually look like they're
measuring some mental ability so here's
here's one so you were bringing that up
as an example as what it is not yes got
it okay so i don't want to go too far
afield on it well too far afield is
actually one of the names of this
podcast so uh
i should mention that far afield far
field uh yeah so anyway sorry so so they
feel the questions look like they they
pass the face validity test and some
more than others and so for example let
me give you a couple of things here
if i
one of the subtests on a standard iq
test is general information
let me just think a little bit because i
don't want to give you the actual item
but if i said how far is it
between
washington dc and miami florida
within 500 miles plus or minus
well you know it's not a fact most
people memorize
but you can you know something about
geography you say well i flew there once
i know planes fly for 500 miles you know
you can get you can kind of make an
estimate
but it's also seems like it would be
very cultural
um you know
so there's that kind of
general information then there's
vocabulary test
what does
uh
regatta mean
and i choose that word because that word
was removed from the iq test because
people complained that disadvantaged
people would not know that word
just from their everyday
life
okay
here's another example from a different
kind of subtest on what's regatta by the
way a regatta is a um
i think this advantage is a sailing
competition a competition with boats not
necessarily sailing but the competition
yep yep okay i'm proudly disadvantaged
in that way okay excellent so that was
removed okay what you were saying okay
so now here's a here's another subtest
i'm going to repeat a string of numbers
and when i'm done i want you to repeat
them back to me
ready
okay
four
two
eight
one
six
that's way too many seven four two eight
one six okay you get the idea now the
actual test starts with
a smaller number
you know like two numbers and then it is
people get it right you keep going
adding to the string of numbers until
they can't do it anymore
okay but now try this
i'm going to re i'm going to say some
numbers and when i'm done i want you to
repeat them to me backwards
i quit
okay
now
so i gave you some examples of the kind
of items on an iq test general
information
um i can't even remember all
general information vocabulary
digits span forward and digit span
backward
well you said i can't even remember that
that's a good question for me
uh what does memory have to do with you
well that's all that's that's all that's
okay all right so let's let's let's just
talk about these
examples now
some of those
items
seem very cultural
and
others seem less cultural
which ones do you think
scores on which subtest are most highly
correlated with the g factor
well the d2 advances less cultural
well
it turns out vocabulary is highly
correlated
and it turns out that digits span
backwards is highly correlated
how do you how do you figure now you
have
decades of research to answer the
question how do you figure
right so no now there's like good
research that gives you intuition about
what kind of questions get at it just
like uh
there's something
i've done
i've actually used for research to send
me a autonomous vehicle like whether
humans are paying attention there's a
body of literature that does like end
back tests for example we have to
um
put workload on the brain to do recall
memory recall and that helps you kind of
put some work onto the brain while the
person is doing some other tasks and
this does some interesting research with
that
but that's loading the memory so there's
like research around
stably
what that means about the human mind and
here you're saying recall backwards
is a good predictor the transformation
yeah so you have to so you have to do
some
some like you have to load that into
your brain and not just remember it but
do something with it right here's
another example of a different kind of
test called the hick paradigm and it's
not verbal at all it's a little box
and there are a series of lights
arranged in a semi-circle at the top of
the box
and then there's a home button that you
press
and when one of the lights goes on
there's a button next to each of those
lights
you take your finger off the home button
and you just press
the button next to the light that goes
on
and so it's a very simple reaction time
light goes on as quick as you can you
press the button and you get a reaction
time from the moment you lift your
finger off the button
when you press
the button with where the light is
that reaction time
doesn't really correlate with iq very
much
but if you change
the instructions
and you say
three lights are going to come on
simultaneously
i want you to press the button next to
the light that's furthest from the other
two
so maybe lights one and two go on and
and light six goes on simultaneously you
take your finger off and you would press
the button by light six
that's
that reaction time to a more complex
task
it's not really hard
almost everybody gets it all right but
the your reaction time to that is highly
correlated with the g factor this is
fascinating so reaction time so there's
a temporal
aspect to this so it's what what role
crossing it's the speed of processing is
this also true for ones that take longer
like 5 10 30 seconds
is time part of the measure with
something yes yes and that is why some
of the best iq tests
have a time limit
because if you have no time limit
people can do better yeah but it doesn't
it doesn't distinguish among people
that well
so that
adding the time element is important so
speed of information processing
turn and reaction time is a measure of
speed of information processing turns
out to be related to the g factor but
the g factor only accounts for maybe
half or some amount on the test
performance for example i get
a
pretty bad test anxiety like i was never
i mean
i just don't enjoy tests i enjoy going
back into my cave
and working like i've always enjoyed
homework
way more than tests
uh no matter how hard the homework is
because i can go back to the cave and
hide away and think deeply there's
something about being watched and having
a time limit that really makes me
anxious and i could just see the mind
not operating optimally at all but
you're saying underneath there there's
still a g factor there's the question
no question
boy
and if you get anxious taking a test
many people say oh i didn't do well
because i'm anxious yeah
you know i hear that a lot yeah well
fine if you're really anxious during the
test
the score will be a bad estimate of your
g factor yeah it doesn't mean the g
factor isn't there that's right and by
the way
standardized tests like the sat
they're essentially intelligence tests
they are highly g-loaded now the the
people who make the s.a.t don't want to
mention that
for obviously they have enough trouble
justifying standardized testing but to
call it an intelligence test is really
beyond the pale but in fact it's so
highly correlated because it's a
reasoning test
sat is a reasoning test a verbal
reasoning mathematical reasoning yeah
and if it's a reasoning test it has to
be related
to to g but if people
go in and take a standardized test
whether it's an iq test or the sat and
they happen to be sick that day with 102
fever
the score
is not going to be a good estimate of
their g if they retake the test when
they're not anxious or less anxious or
don't have a fever
the score will go up and that will be a
better estimate but you can't say their
g factor increased between the two tests
well it's interesting so the question is
how wide of a battery of tests is
required to estimate the g factor well
because i'll give you as my personal
example i took the sat
and i think it was called the act where
i was too also i took sat many times
every single time i got perfect on math
and verbal
the time limit on the verbal made me
very anxious
i did not i mean part of it i didn't
speak english very well
but honestly it was like you're supposed
to remember stuff and like i was so
anxious and like as i'm reading i'm
sweating i can't you know that like um
that feeling you have when you're
reading a book and you
you just read a page and you know
nothing about what you've read because
you zoned out that's the same feeling of
like
i can't i have to you're like nope
read and understand and that anxieties
like
and you start seeing like the typography
versus the content of the words like
that was
i i don't it's interesting because
um
i know that
what they're measuring i could see being
correlated with something but that
anxiety or some aspect of the
performance
um
sure plays a plays a factor and
i wonder how you sneak up in a stable
way i mean this is a broader discussion
about
that's like uh standardized testing how
you sneak up
how you get
at the fact that i'm super anxious and
still nevertheless measure some aspect
of my intelligence i wonder i don't i
don't know i don't know if you can say
it to that that time limit sure is a
pain
well let me say this
there are two ways to approach
the very real problem that you say that
some people just get anxious or not good
test takers
by the way
part of
part of testing is
you know the answer you can figure out
the answer or you can't
right if you don't know the answer there
are many reasons you don't know the
answer at that particular moment you may
have learned it once and forgotten it
you may it may be on the tip of your
tongue and you just can't get it because
you're anxious about the time limit you
may never have learned it
you may never you you may have been
exposed to it but it was too complicated
and you couldn't learn it i mean there
are all kinds of reasons here
but for an individual to interpret your
scores
as an individual
whoever is interpreting the score has to
take into account
various things that would affect your
individual score and that's why
decisions about college admission
or anything else where tests are used
are hardly ever the only
criterion
to make a decision and i think people
are a college admission is letting go of
that very much oh yes there yeah but
what does that even mean because um
is it possible to design standardized
tests
that do get that are useful to college
admissions well they already exist the
sat is highly correlated with many
aspects of success at college here's the
problem so maybe you could speak to this
the correlation across the population
versus individuals
so
you know our criminal justice system is
designed
to make sure
uh
well
it's it's it's still there's tragic
cases where innocent people go go go to
jail but you try to avoid that in the
same
uh way with testing it just
it would suck for an sat to miss genius
yes and it it's possible but it's
statistically unlikely so the so it
really comes down to
yeah do which
piece of information
maximizes
your
decision making ability
so
if you just use high school grades
it's okay
but you will miss some people who just
don't do well in high school but who are
actually
pretty smart smart enough to be bored
silly in high school and they don't care
and they their high school gpa isn't
that good so you will miss them
in the same sense
that somebody who could be
very
able and ready for college just doesn't
do well on their s.a.t this is why
you make decisions with of
taking in a variety of in information
the other thing i wanted to say
you know we talked about when you make a
decision for an individual
statistically
for groups there are many people
who have a disparity between their math
score and their verbal score that
disparity or the other way around that
disparity is called tilt
the score is tilted one way or the other
and that tilt has been studied
empirically to see what that predicts
and in fact you can't make predictions
about
about college success
uh based on on tilt and mathematics is a
good example there are many people
especially non-native speakers of
english who come to this country take
the sats do very well on the math and
not so well on the verbal
well if they're applying to a math
program
the professors there who are making the
decision or the admissions officers
don't wait so much to score on verbal
especially if it's a non-native speaker
well so yeah you have to
try to in the admission process bring in
the context
but non-native isn't really the problem
i mean that was part of the problem for
me
but it's the the anxiety was which it's
interesting
it's interesting
um
oh boy reducing yourself down to numbers
but it's still true it's still the truth
well it's a it's a painful that same
anxiety that led me to be
um to struggle with the sat uh
verbal tests
is still within within me
in all ways of life
so maybe that's not anxiety
maybe that's something um you know like
personality
is also pretty stable
personality is stable
personality uh does impact
the way you navigate life yeah uh
there's no question
yeah and and we should say that g factor
in intelligence is not just about some
kind of
um
number on a paper
it also has to do with
how you navigate life
how
um
easy life is for you
in this very complicated world so
personality is all tied into that in
some in some some deep fundamental way
but now you've hit the key point about
why we even want to study intelligence
and personality i think to a lesser
extent but
that's my interest is more on
intelligence i went to graduate school
and wanted to study personality but
that's kind of another story how i got
kind of shifted from personality
research over to intelligence research
because it's not just a number
intelligence is not just an iq score
it's not just an sat score it's what
those numbers reflect
about your ability to navigate everyday
life
it has been said
that life is one long intelligence test
[Laughter]
and who can't relate to that
and if you doubt see another problem
here is a lot of critics of intelligence
research intelligence testing
tend to be academics who by and large
are pretty smart people
and pretty smart people by and large
have enormous difficulty understanding
what the world is like for people with
iqs of 80
or 75
it is a completely different everyday
experience
even
iq scores of 85 90
you know there's a popular television
program judge judy where judge judy
deals with
everyday people with everyday problems
and you can see the full range
of problem-solving ability demonstrated
there
and sometimes she does it for laughs but
it really isn't funny because
people
who who are are
there are people who are very limited in
their life
navigation let alone success
by having
by by not having good reasoning skills
which cannot be taught
we know this by the way because there
are many efforts you know the united
states military which excels at training
people
i mean i don't know that there's a
better organization in the world for
training diverse people
and they won't take people with iqs
under i think 83 is the cut off
because they have found you
they are unable to train
people with lower iqs to do jobs in the
military so one of the things that g
factor has to do with his learning
absolutely some people learn
faster than others
some people learn more than others now
faster by the way is not necessarily
better
as long as you get to the same place
eventually
but you know there are professional
schools that want students who can learn
the fastest because they can learn more
or learn deeper or
all kinds of
of
ideas about why you select people with
the highest scores and there's nothing
funnier by the way to listen to a bunch
of academics complain about the concept
of intelligence and intelligence testing
and then you go to a faculty meeting
where they're discussing who to hire
among the applicants and all they talk
about is how smart the person is
we'll get to that we'll sneak up to that
in different ways but there's something
about reducing a person to a number that
in part is grounded to the person's
genetics that makes people very
uncomfortable but nobody does that
nobody in the field actually does that
that is a that is a worry
that
is
a worry
like
um
well i don't want to call it a
conspiracy theory i mean it's a
legitimate worry
but it just doesn't it just doesn't
happen now i had a professor in graduate
school who was the only person i ever
knew who
considered the students only by their
their test scores
yes and later in his life he kind of
backed off that
but
um well let me ask you this so we'll
jump around
i'll come back to the book
i tend to uh i've had like political
discussions with people
and um
actually uh my friend michael malus he's
uh he's an anarchist
i disagree with him on basically
everything except um
the fact that
love is a beautiful thing in this world
and he says this test about left versus
right whatever it doesn't matter what
the test is but um
he believes the question is do you
believe that some people are better than
others
the question is
uh ambiguous
do you believe some people are better
than others and to me sort of the
immediate answer is
no
it's a poetic question it's ambiguous
question right
like uh you know people want to maybe
the temptation to ask better what better
like sports so on
no uh to me
i stand with the sort of
defining documents of this country
which is all men are created equal
there's a basic humanity and there's
something about
tests of intelligence
just knowing that some people are
different like the science of
intelligence that shows that some people
are genetically
in some stable way across a lifetime
have a greater intelligence than others
makes people feel
like some people are better than others
and that makes them very uncomfortable
and i
maybe you can speak to that like
the fact that some people are more
intelligent than others in a way that's
um
cannot be compensated
through
education
through anything you do in life
um
what do we do with that
okay there's a lot there
we haven't really talked about the
genetics of it yet but you are
correct uh
in that it is my interpretation of of
the data
that genetics has a very important
influence on the g factor and this is
controversial we can talk about it but
if you think that genetics the genes are
deterministic are always deterministic
that leads to kind of the worry that you
expressed
but we know
now in the 21st century that many genes
are not deterministic that are
probabilistic
meaning they
their their uh
gene expression can be
uh influenced
uh now whether they're influenced only
by other biological variables
or other genetic
variables or environmental or cultural
variables that's where the controversy
comes in
and we can come we can discuss that in
more detail if you like but to go to the
question about better
people better
there's zero evidence
that
smart people
are better
with respect to
important aspects of life
like honesty
even likability
i'm sure you know many very intelligent
people who are not terribly likable or
terribly kind or terribly honest
is there something to be said so one of
the things i've recently re-read for the
second time
i guess that's what the word reread
means
the rise and fall of the third reich uh
which is
i think the best telling of the rise and
fall of hitler
and one of the interesting things about
the people that
uh
how should i say it
um
justified
or maybe propped up the ideas that
hitler put forward
is the fact that they were extremely
intelligent
they were in the intellectual class
they were
like it was obvious that they they
thought very deeply and rationally about
the world so what i would like to say is
one of the things that shows to me is
some of the worst atrocities in the
history of humanity have been committed
by very intelligent people
so that that means that intelligence
doesn't make you a good person i wonder
if
um
you know there's a g factor for
intelligence i wonder if there's a g
factor for goodness
uh you know the niche uh good and evil
of course that's probably harder to
measure
because that's such a subjective thing
what it means to be good
and even the idea of evil is
a deeply uncomfortable thing because how
do we know
but it's independent whatever it is it's
independent of intelligence so i i agree
with you about that but let me say this
i have also
asserted
my belief
that more intelligence is better than
less
that doesn't mean more
intelligent people are better people
but all things being equal would you
like to be smarter or less smart so if i
had a pill i have two pills i said this
one will make you smarter this one will
make you dumber which one would you like
are there any circumstances under which
you would choose to be dumber well let
me ask you this
that's a very nuanced and interesting
question
you know there's been books written
about this right
um now we'll return to the hard
questions the interesting questions but
let me ask about human happiness
this
intelligence lead to happiness no
so so okay so back to the pill then
so why
uh when would you take the pill so you
said iq 80
90 100
110 you start going to the quartiles and
um is it obvious
isn't there uh
diminishing returns and then it starts
becoming negative
this is an empirical question
yes and so that i have advocated
in many forums
more research
on
enhancing the g factor
right now there's
there have been many claims about
enhancing intelligence
with you mentioned the n-back training
it was a big deal a few years ago it
doesn't work
data is very clear it does not work
you know or doing like memory tests like
training and so on yeah yeah it makes it
may give you a better memory in the
short run
but it doesn't impact your
g factor
um it was very popular a couple of
decades ago that
the idea that listening to mozart
could make you more intelligent there
was a paper published on this with
somebody i knew published this paper
uh intelligence researchers never
believed it for a second
been hundreds of studies all the meta
analyses all the summaries and so on so
there's nothing to it
nothing to it at all
but but but wouldn't it be something
wouldn't it be world
shaking
if you could take the normal
distribution of intelligence which we
haven't really talked about yet but
iq scores and the g factor is thought to
be a normal distribution
and shift it to the right so that
everybody
is smarter
even a half a standard deviation would
be world shaking
because there are many social problems
many many social problems
that are exacerbated
by people
with lower
ability to reason stuff out
and navigate everyday life
so i wonder if there's a threshold so
maybe
i would push back and say
universal shifting
of the
normal distribution may not be the
optimal way of shifting
maybe it's better to uh whatever the
asymmetric tank kind of distributions is
like really pushing the lower up
versus uh trying to make the
uh people at the average more
intelligent so you're saying that if in
fact there was some way to increase g
let's just call it metaphorically a pill
an iq pill
we should only give it to people at the
lower end
no it's just intuitively
i i can see that life becomes easier at
the lower end yes if it's increased
it becomes less and less it is an
empirical scientific question but it
becomes less and less obvious to me that
more intelligence
is better
at the high end
it not because it would make life easier
but it would make whatever problems
you're working on
more solvable
and if you are working on artificial
intelligence there's a
tremendous potential
to good for for that to improve society
i understand
so
at that whatever problems you're working
on
yes
but there's also the problem of the
human condition
there's
love there's fear and all those
beautiful things that sometimes if
you're good at
solving problems you're going to create
more problems for yourself it's uh
i'm not exactly sure so ignorance is
bliss is a thing so there might be a
place there might be a sweet spot of
intelligence
given your environment given your
personality all those kinds of things
and that becomes less
beautifully complicated the more and
more intelligent
you become but that's a that's a that's
a question for literature not for
science perhaps
imagine this imagine there was an iq
pill yeah and it was developed by a
private company
and they are willing to sell it to you
and whatever price they put on it you
are willing to pay it because you would
like to be smarter yes but just before
they give you a pill
they give you a disclaimer form to sign
yes
don't hold us
that we
you understand that this pill has no
guarantee that your life is going to be
better and in fact it could be worse
well yes that's how lawyers work but i
would love for science to answer the
question
to try to predict if your life is going
to be better or worse
when you become more uh more or less
intelligent it's a it's a fascinating
question about what is the sweet spot
for the human condition
uh some of the things we see as
bugs might be
actually features maybe crucial to our
uh overall happiness is our limitations
might lead to more happiness than less
but again more intelligence is better at
the lower end that's more that's as
that's something that's less arguable
and
and and fascinating if possible to
increase but you know there's virtually
no research
that's based on a neuroscience approach
to solving that problem
all the solutions that have been
proposed
to solve that problem or to ameliorate
that problem are essentially based on
the blank slate assumption
that you know enriching the environment
removing barriers
all good things by the way i'm not
against any of those things but there's
no empirical evidence that they're going
to improve
the general reasoning ability
or make people more employable
have you read flowers of uh argan on yes
that's to the question of intelligence
and happiness
there are many profound aspects of that
story it was a film that was very good
uh if the film was called charlie for
the younger people who are listening to
this
uh
you might be able to stream it on
netflix or something but
it was a story about
uh a person with very low iq who
underwent a surgical procedure in the
brain and he slowly became a genius
and the tragedy of the story is the
effect was
temporary
it's a fascinating story really that
goes in contrast to the the basic human
experience that each of us individually
have but it raises the question of
the
the full
the full range of people you might be
able to be
uh given different levels of
intelligence you've mentioned
the normal distribution
so let's talk about it
there's a book called the bell curve
written in 1994
written by psychologist richard
hernstein and political scientist
charles murray
why was this book so controversial
this is a fascinating book
i know charles murray
i've had many conversations with with
him yeah what is the book about with the
book is about
the importance of intelligence
in everyday life
that's what the book is about
it's an empirical book it has uh
statistical analyses of very large
databases that show that
essentially
iq scores or their equivalent are
correlated to all kinds of social
uh problems
uh and social benefits
and
that in itself is not where the
controversy about that book came
the controversy was about one chapter in
that book
and that is a chapter about the
average difference in mean scores
between black americans and white
americans
and these are the terms that were used
in the book at the time and are still
used to some extent
and
historically
or really for decades
it has been observed
that uh disadvantaged groups
uh score on average
lower
than caucasians
on
on academic tests tests of mental
ability and especially on iq tests
and the difference is about a standard
deviation which is about 15 points which
is a substantial difference
in the book
hernstein and murray in this one chapter
assert
clearly and unambiguously
that whether this
average difference is due to genetics
or not
they are agnostic they don't know
moreover they assert they don't care
because you wouldn't treat anybody
differently knowing
that if there was a genetic component or
not because that's a group average
finding every individual has to be
treated as an individual you can't make
any assumption
about what that person's intellectual
ability might be
from the fact of a average group
difference they're very clear about this
nonetheless
people
took away
i'm going to choose my words carefully
because i have a feeling that many
critics didn't actually read these
read the book
they took away that hernstein and murray
were saying that blacks are genetically
inferior
that was the take home message and if
they weren't saying it they were
implying it because they had a chapter
that discussed this empirical
observation of a difference
and
isn't this horrible
and so the reaction to that book
was
incendiary
what do we know
about
from that book and the research beyond
uh about race differences
and intelligence it's still the most
incendiary topic in psychology nothing
has changed that anybody who even
discusses it is easily
called a racist just for discussing it
it's become fashionable to find racism
in
any discussion
like this
it's unfortunate
the short answer to your question is
there's been very little actual research
on this topic
since 19
since the book of
since the bell curve even before
this really became incendiary
in 1969 with an article published by an
educational psychologist named arthur
jensen
let's just take a minute and go back to
that
to see the bell curve in a little bit
more historical perspective
arthur jensen was a educational
psychologist at uc berkeley i knew him
as well
and um
in 1969 or 68 the harvard educational
review
asked him
to
take an uh to do a review article on the
early childhood education programs that
were designed to raise the iqs
of minority
students
this was before the federally funded
head start program head start had not
really gotten underway at the time
jensen undertook his review of what were
a number of demonstration programs
and these demonstration programs
were
for young children around kindergarten
age and they were specially designed to
be cognitively stimulating to provide
lunches
do all the the things that people
thought would
uh minimize this this average gap of
intelligence tests there was a a strong
belief
among virtually all psychologists
that the cause of the gap was unequal
opportunity due to racism due to all you
know all negative things in the society
and if you could
compensate for this the gap would go
away
so early childhood education back then
was called literally compensatory
education
jensen looked at these programs he was
an empirical guy he understood
psychometrics
and he wrote a it was over a hundred
page article detailing
these programs and the flaws in their
research design
some of the programs reported iq gains
of on average five points but a few
reported 10 20 and even 30 point gains
one was called the miracle in milwaukee
the that investigator went to jail
ultimately for fabricating data
but the point is that jensen wrote an
article that said look
uh the opening sentence of his article
is classic the opening sentence is i may
not quote it exactly right but it's we
have tried compensatory education and it
has failed
and he showed that these games
were essentially nothing
you couldn't really document
empirically any gains at all from these
really earnest efforts
to increase iq
but
he went a step further a fateful step
further
he said not only
have these efforts failed but because
they have had essentially no impact we
have to re-examine our assumption that
these differences are caused by
environmental things that we can address
with education we need to consider
a genetic influence whether there's a
genetic influence on this group
difference so you said that this is one
of the more controversial
works i think the most infamous paper in
all of psychology
i would go on to say
because in 1969
the genetic
data was very skimpy on this question
skimpy and controversial it's always
been controversial but it was even
skimpy and controversial
it's kind of a long story that i go into
a little bit in more detail in
the book neuroscience of intelligence
but
to say he was vilified is an
understatement i mean he couldn't talk
it at the american psychological
association
without bomb threats clearing the the
lecture hall
campus security watched him
all the time they opened his mail
he had to retreat to a different address
this was
one of the earliest kinds this is before
the internet and and kind of internet
social media mobs
but it was that intense
and
i have written that overnight
after the publication of this article
all intelligence research became
radioactive
nobody wanted to talk about it
uh and then it it it didn't
it
nobody was doing more research
and then the bell curve came along and
the johnson controversy was dying down i
have stories that jensen told me about
his interaction with the nixon white
house on this issue i mean it was this
was like a really big deal
it was some unbelievable stories but you
know he told me this so i kind of
believe these stories
nonetheless
25 years later 25 years later all the
silence basically saying you know this
uh nobody wants to do this kind of
research there's so much pressure so
much attack against this kind of
research
and here's uh
sort of a bold stupid crazy people that
decide to dive right back in and i
wonder how much discussion that was do
we include this chapter or not
murray has said they discussed it and
they felt
they should include it
and they were very careful in the way
they they wrote it which did them no
good
yeah
so
as a matter of fact when the bell curve
came out it was so controversial i got a
call
from a television show called nightline
it was with a broadcaster called ted
koppel who had this evening show i think
was on late at night talked about news
it was a straight up news thing yeah and
producer called and asked if i would be
on it to talk about the uh the bell
curve
and i said you know it it
she asked me what i thought about the
bell curve as a book i said look it's a
very good book it talks about the role
of intelligence in society
and she said no no what do you think
about the chapter on race that's what we
want you to talk about
i remember this conversation
i said well
she said what would you say if you were
on tv
and i said well
what i would say is that it's not at all
clear if there's any genetic component
to intelligence
um
any differences but if there were a
strong genetic component that would be a
good thing
and you know complete silence on the
other end of the phone yeah and she said
well what do you mean
and i said well if it's the more genetic
any difference is the more it's
biological
and if it's biological we can figure out
how to fix it
i see that's interesting she said would
you say that on television yes i said no
and so that was the end of that so
that's for more like uh biology
is
um
within the reach of science
and
the environment is a public policy
social and all those kinds of things
it's it from your perspective whichever
one
you think is more amenable to solutions
in the in the short term is the one that
excites you
but
um you're saying that it's good
uh
the truth of genetic differences
no matter what the
between groups
is is a
painful
harmful
potentially potentially dangerous thing
so let me ask you to this
question whether there's bell curve or
any research on
race differences
can that be used to increase the amount
of racism in the world
can that be used to increase the amount
of hate in the world do you think about
this kind of stuff i've thought about
this a lot not as a scientist but as a
person
and
my sense is
there is such
enormous
reservoirs of hate and racism
that have nothing to do with scientific
knowledge of the data
that speak against that
that
no i don't
i don't want to give racist groups of
veto power over what scientists study
if you think that the differences
and by the way virtually no one
disagrees that there are differences in
scores it's all about what causes them
and how to fix it
so if you think this is a cultural
problem then you must ask the problem
what do you want do you want to change
anything about the culture or are you
okay with
the culture because you don't feel it's
appropriate to change a person's culture
so are you okay with that and the fact
that that may lead to disadvantages in
in school achievement
it's a question
are if you think it's environmental
what are the environmental
parameters that can be fixed i'll tell
you one
lead in you know led from gasoline in
the atmosphere lead in paint lead in in
water
that's an environmental toxin that
society has the means to
eliminate
and they should yeah just to sort of
trying to find some
insight and conclusion to this very
difficult topic
uh is there
been research on environment versus
genetics nature versus nurture on this
question of race differences
there is not no one wants to do this
research it's first of all it's hard
research to do second of all it's it's a
minefield no one wants to spend their
career on it tenured people don't want
to do it let alone students
the way i talk about it
i well before i tell you the way i talk
about i want to say one more thing about
jensen
he was once asked by a journalist
straight out are you a racist
his answer was very interesting his
answer was i've thought about that a lot
and i've concluded it doesn't matter
this now i i know what he meant by this
the guts to say that wow he was a very
unusual person i think he had a touch of
asperger's syndrome to tell you the
truth because i i saw him in many
circumstances he would be cancelled on
twitter immediately with that sentence
yeah but what he what he meant was he
had a hypothesis
yeah and with respect to group
differences he called it the default
hypothesis he said whatever factors
affect individual intelligence are
likely the same factors that affect
group differences it was the default but
it was a hypothesis
it should be tested and if it turned out
empirical test didn't support the
hypothesis he was happy to move on to
something else
he was absolutely committed to that
scientific ideal
that that
it's an empirical question we should
look at it and let's see what happens
the scientific method cannot be racist
from his perspective it doesn't matter
what the scientists
if they
if they follow the scientific method
it doesn't matter what they believe and
if they are biased and they
consciously or unconsciously
bias the data
other people will come along to
replicate it they will fail and the
process over time
will work
so let me push back on this
idea
because psychology to me
is full of gray areas
and what i've observed about psychology
even replication crisis aside
is that something about the media
something about journalism
something about the the virality of
ideas in the public sphere
they
misinterpret
they take up things from studies
willfully or from ignorance misinterpret
findings
and tell narratives around that
i personally believe for me i'm not
saying that broadly about science but
for me
it's my responsibility to anticipate the
ways in which findings will be
misinterpreted
so
i've had i thought about this a lot
because i
publish papers on
uh semi-autonomous vehicles and
those
you know cars people dying cars
there's people that have written me a
letter saying emails nobody writes
letters i wish they did
uh that i have blood in my hands because
of things that i would say positive or
negative there's consequences in the
same way when you're a researcher for
intelligence
i'm sure you might get emails
or
at least people might believe that
finding your study
is going to be used by a large number of
people to increase the amount of hate in
the world
i think there's some responsibility on
scientists
but for me i think there's a great
responsibility
to anticipate the ways
things will be misinterpreted
and there you have to
first of all decide whether you want to
say a thing at all
or do the study at all publish the study
at all and to the words with which you
explain it
it's uh
i find this on twitter a lot actually
which is when i when i write a tweet i'm
usually just doing so innocently
i
i'll
i'll i'll write it you know it takes me
like five seconds to write it or
whatever 30 seconds to write it and then
i'll think all right i like close my
eyes
open and try to see how will the world
interpret this like what are the ways in
which this will be misinterpreted and
i'll sometimes adjust that tweet to see
like yeah so in my mind it's clear but
that's because it's my mind from which
this tweet came but you have to think in
a fresh mind that sees this
uh and it's spread across
a large
number of other minds how will
the interpretation morph i mean for a
tweet it's a silly thing it doesn't
matter but for
a scientific
paper and study and finding
i think it matters
so i don't know i don't know what your
thoughts about that because maybe for
jensen
uh the data is there
what do you want me to do this is a
scientific
process has been carried out
if you think the data was polluted by
bias do other studies that reveal the
bias
uh but the data is there and we like i
have
would i'm not a poet
i'm not a uh literary right like what do
you want me to do i'm just presenting
you the data what do you think on that
spectrum what's the role of a scientist
the reason i do podcasts yeah the reason
i write
books for the public
is to explain what i think the data mean
and what i think the data don't mean
i don't do very much on twitter other
than to retweet uh references to papers
yes i don't think it's my role to
explain these because they're
complicated they're nuanced
but when you decide
not to do a scientific study because
you're
or not to publish a result because
you're afraid the result
could be
could be harmful or insensitive
that's not an unreasonable thought
and
people will
make different conclusions and decisions
about that
i wrote about this i wrote
i i'm the editor of a journal called
intelligence which published which
publishes scientific papers
sometimes we publish papers on group
differences
those papers sometimes are controversial
these papers are written for a
scientific audience they're not written
for the twitter audience so i don't
promote them very much on
on twitter
but
in a scientific paper
you have to now choose your words
carefully also because those papers are
picked up
uh by non-scientists
by writers of various kinds and you have
to be available to discuss
what you're saying and what you're not
saying
sometimes
you are successful at having a good
conversation like we are today that's
that doesn't start out pejorative
other times i've been asked to
participate in debates where my role
would be to justify race science
well you can see
just start out
you know and that was a bbc request that
i had that i received i have so much
it's a love-hate relationship mostly
hate with these shallow journal uh
journalism organizations so they would
want to use you
as a kind of in a debate setting to
communicate as to like there is raise
differences between groups and make that
into debate yes and put you in a role of
um justifying racism you justify that's
what they're asking me to do courses
like educating about this this field of
the science of intelligence yeah i i
want to say one more thing before we get
off the the normal distribution you also
asked me
what is the science after the bell curve
and the short answer is there's not much
new work but whatever work there is
supports the idea that there still are
group differences it's arguable whether
those differences have diminished at all
or not
and there is still a major problem in
underperformance in for school
achievement
for many uh mis disadvantaged and
minority students and there's so far is
no way to fix it
uh what do we do with this information
what uh is this is this now a task now
we'll talk about the future
uh on the neuroscience and the biology
side but in terms of this information as
a society in the public policy in the
political space in the social space what
do we do with this information
i've thought a lot about this the first
step
is to have people interested in policy
understand what the data actually show
to pay attention to intelligence data
you can read policy papers about
education and using your word processor
you can search for the word intelligence
you can search a twenty thousand word
document in a second
and find out the word intelligence does
not appear
anywhere
in most discussions about what to do
about achievement gaps i'm not talking
about test gaps i'm talking about actual
achievement gaps in schools which
everyone agrees is a problem the word
intelligence doesn't appear among
educators
that's fascinating as a matter of fact
in california
there has been tremendous controversy
about recent attempts to revise the
curriculum for math
in high schools
and we had a stanford professor of
education who was running this
review
assert there's no such thing as talent
of mathematical talent
and she wanted to
get rid of the advanced classes in math
because you know not everyone could do
that
now of course this has been very
controversial they've retreated somewhat
but the idea that a university professor
was in charge of this who believes
not that there's no
talent
that doesn't exist
this is rather shocking let alone the
complete absence of intelligence data by
the way let me tell you something about
what the intelligence data show
let's take race out of it
uh even though the origins of these
studies uh were
a long time ago um
i'm blocking on the name of the report
the coleman report was a famous report
about education and they measured all
kinds of variables about schools
about teachers
and they looked at
academic achievement as an outcome
and they found
the most predictive variables of
education
outcome were the variables the student
brought
with him or her into the school
essentially their ability
and that when you combine the school and
the teacher variables together
the quality of the school the funding of
the school the quality of the teachers
their education you put all the teacher
and school variables together it barely
accounted for 10 of the variants
and this has been replicated now
you know so
the best research we have
shows that school variables and teacher
variables together
account for about 10 of student academic
achievement
now
you want to have some policy on
improving academic achievement how much
money do you want to put into teacher
education how much money you want to put
into
the quality of of of the school
administration you know who you can ask
you can ask the gates foundation
because they spent a tremendous amount
of money doing that
and they
at the end of it because they're
measurement people they want to you know
they want to know the data they found it
had no impact at all and they've kind of
pulled out of of that kind of program
so oh boy
let me ask let me ask you
this is me talking but there's
just the two of us well just the two of
us but i'm gonna say uh some funny and
ridiculous things so it's
you're surely you're not approving of it
uh but there's a movie called clerks
you probably i've seen it i've seen it
yeah there's a funny scene in there
where a lovely couple are talking about
the number of previous sexual partners
they had
and uh
uh the woman says that i believe she
just had a handful like two or three or
something like that sexual partners but
then she also mentioned
um that she um
what's that called fellatio what's the
scientific but she went you know gave a
to uh 37 guys i believe it is
and
so that has to do with the truth
so sometimes
knowing the truth
can get in the way of a successful
relationship of love of some of the
human flourishing
and that's
seems to me that's at the core here that
facing some kind of
truth that's not
able to be changed
it makes it difficult to sort of
it's limiting as opposed to empowering
that's the concern if you sort of test
for intelligence and lay the data out
it feels like you will give up on
certain people
you will
you'll sort of start bidding people it's
like well this is this person is like
let's focus on the average people or
let's focus on the very intelligent
people that's the concern
and and there's a kind of
intuition that if we just don't measure
and we don't use that data then we would
treat everybody equal and give everybody
equal opportunity
if we have the data in front of us we're
likely to
misdistribute
the amount of sort of attention we
allocate resources we allocate uh
allocate to people that's that's
probably the concern
it's a realistic concern
and but i think it's a misplaced concern
if you want to fix the problem
if you want to fix the problem you have
to know what the problem is
now let me let me tell you this let's go
back to the bell curve for not the bell
curve but the normal distribution yes
of the population on average has an iq
under 85
which means they're very hard if you
have an iq under 85 it's very hard to
find gainful employment at a salary
sustains you at least minimally in
modern life
okay not impossible but it's very
difficult
of the population of the united states
is about 51 or 52 million people with
iqs under 85.
this is not a small issue
14 million children have iqs under 85.
is this something we want to ignore
does this have any what is the venn
diagram between
you know when you have people with iqs
under 85 and you have
achievement in school
or achievement in life
there's a lot of overlap there
this is why to go back to the iq pill if
there were a way
to shift
that
curve
toward the higher end
that would have a big
impact if i could maybe before we talk
about the impact on life and so on
um some of the criticisms of the bell
curve so stephen j good wrote that the
bell curve rests on four incorrect
assumptions
it would be just interesting to get your
thoughts on the four assumptions which
are
intelligence must be reducible to a
single number intelligence must be
capable of rank ordering people in a
linear order intelligence must be
primarily genetically based and
intelligence must be essentially
immutable um maybe not as criticisms but
as
thoughts about intelligence
yeah that we could we could spend a lot
of time on him
yeah he wrote that in what about 1985
1984.
he his views were overtly political not
scientific he was a scientist but his
views on this were overtly political and
i would encourage
people listening to this if they really
want to understand
his criticisms
they should
just
google
what he had to say
and google the scientific
reviews of his book
the mismeasure of man and they will take
these statements apart they were wrong
not only were they wrong but when he
asserted in his first book that you know
that there was no biological basis
essentially to iq
by the time the second edition came
around there were studies of mri
mris of showing that brain size brain
volume were correlated to iq scores
which he declined to put in his book
so i'm learning a lot today i didn't
know
i didn't know the actually the extent of
his work i was just using a few little
snippets of criticism that's interesting
so there's a battle here he wrote a book
miss measure of man
that's not that's missing a lot of these
scientific uh
his grounding book is highly popular in
colleges today you can find it in any
college bookstore under a signed reading
it's highly popular in this measure of
men yes highly influential can you speak
to the miss measurements i'm i'm
undereducated about this so what is this
the book basically criticizing yeah the
ideas in the bulk yeah yeah where those
four things came from
and it is really um a book that was uh
really taken apart point by point by a
number of people who actually understood
the data and he didn't care
yeah he didn't care he didn't
it's a politically listen
uh because this is such a sensitive
topic
like i said i believe
uh
the the impact of the work
as it is misinterpreted has to be
considered
because it's not just going to be
scientific discourse it's going to be
political discourse there's going to be
debates there's going to be
politically motivated people that will
use messages in each direction make it
the make something like the bell curve
the enemy
or the support for your uh for for one's
racist beliefs
and so
uh i think you have to consider that but
it's difficult because
you know nietzsche was used by hitler to
justify a lot of his beliefs and it's
not in it's not exactly unneeded to to
anticipate hitler so uh or how his ideas
will be misinterpreted and used for evil
but there is a balance there so i
understand this is really interesting i
didn't i didn't know is there any
criticism of the book you find
compelling or interesting or challenging
to you from a scientific perspective
there were factual criticisms
about the nature of the statistics that
were used the statistical analyses these
were more technical criticisms and they
were
addressed by murray in a couple of
articles where he took all the
criticisms
and and spoke to them and people
listening to this podcast
uh can certainly find all those online
uh it's very interesting but murray went
on to write some additional books two in
the last couple of years
uh one about human diversity
where he goes through the data
refuting the idea that race is only a
social construct with no biological
meaning he he discusses the data it's a
very good discussion you don't have to
agree with it but he presents data in a
cogent way
and he talks about the critics of that
and he talks about their data in a
cogent
non-personal way it's it's a it's a very
informative discussion a book is called
human diversity he talks about race and
he talks about gender same thing about
sex differences
and more recently he's written what
might be his final say on this a book
called facing reality
where he talks about this again
uh
so you know he he can certainly defend
himself he doesn't need me to
to do that but i would urge people who
have heard
about
him and the bell curve
and who think they know what's in it
you are likely incorrect and you need to
read it for yourself
but it is
uh so scientifically it's a
it's a serious subject it's a difficult
subject ethically it's a difficult
subject
everything you said here calmly and
thoughtfully is difficult this is
difficult for me to even
consider that g factor exists
um i don't mean from like that somehow g
factors inherently racist or sexist or
whatever
it's just
it's it's difficult in the way that
concerning the fact that we die one day
is difficult that we are
limited by our biology
it's difficult and it's um
at least from an american perspective
you like to believe that everything is
possible in this world
well that leads us to
what i think
we should do with this information
[Laughter]
and what i think we should do with this
information
is
unusual
uh oh
because i think what we need to do is
fund more neuroscience research on the
molecular biology of learning and memory
because
one definition of intelligence
is based on how much you can learn and
how much you can remember
yes and if you accept that definition of
intelligence
then there are molecular studies
going on now
and nobel prize is being won
on
molecular biology or molecular
neurobiology of learning and memory
now the step those researchers those
scientists need to take when it comes to
intelligence
is to focus on the concept of individual
differences
intelligence
research
has individual differences as its heart
because it it
is it assumes that people differ on this
variable and those differences are
meaningful and need
understanding
cognitive psychologists
who have morphed into molecular
biologists studying learning and memory
hate the concept of individual
differences historically
some now are coming around to it
i once sat next to
a nobel prize winner
for his work on uh on on memory and i
asked him
about uh individual differences and he
said don't go there it'll set us back 50
years
but i said i said don't you think
they're the key though to understand why
can some people remember more than
others he said you you don't want to go
there i think the 21st century will be
remembered by the technology and the
science that
goes to individual differences because
we haven't we have now data we have now
the tools that much much better to start
to measure stuff to estimate uh not just
on the sort of through tests and
like iq test type of things sort of uh
outside the body kind of things but
measuring all kinds of stuff about the
body so yeah truly going to the
molecular biology to the
neurobiology to the neuroscience
let me ask you about in
the
life
does intelligence correlate
uh with or lead to or has anything to do
with career success you've mentioned
these kinds of things and
um is there any data
you've had an excellent conversation
with jordan peterson for example is
there any
data on what intelligent means for
success in life
success in life there is a
tremendous amount of validity data
that looked at
intelligence test scores
and
various measures of
life success
now of course life success is a pretty
broad
topic
and not everybody agrees on
you know what success means but there's
general agreement on certain aspects of
success
that can be measured
uh
and uh including life expectancy like
you said life expectancy now there's
life success uh
you know
uh life expectancy uh
i mean though
that is such an interesting finding but
it you know iq scores are also
correlated to things like income
now okay so who thinks
income means you're successful that's
not the point the point is that income
is one
empirical measure
in this culture
that says something about your level of
success now you can define success in
ways that have nothing to do with income
you can define success
based on your evolutionary natural
selection
success you know you but for variables
uh yeah and even that by the way is
correlated to iq in in in some uh
studies
so
however you want to define success
iq is important
it's not the only determinant people get
hung up on well what about personality
what about so-called emotional
intelligence yes all those things matter
the thing that matters
empirically the single thing that
matters the most is your general uh
ability your general mental intellectual
ability your reasoning ability and the
more complex your vocation
the more complex your job the more g
matters
g doesn't matter in a lot of occupations
don't require complex thinking
and there are occupations like that and
g doesn't matter within an occupation
the
g might not matter so much
so that if you look at
all the professors at mit
and had a way to rank order them on you
know
there's a ceiling effect is what i'm
saying
that you know
also when you get past a certain
threshold then there's impact on wealth
for example or career success
uh however that's defined in each
individual discipline but
after a certain point it doesn't matter
actually it does matter in certain
things so for example there is a very
classic study
uh that was started at johns hopkins
when i was a graduate student there i
actually worked on this study at the
very beginning the study of
mathematically and scientifically
precocious youth
and they gave
junior high school students age
11 and 12
the
standard s.a.t math exam
and they found a very large number of
students
scored very high on this exam
not a large number i mean they they
found many students when they cast the
net to all of baltimore they found a
number of students who scored as high on
the s.a.t math when they were 12 years
old as incoming hopkins freshmen
and they said gee now this is
interesting
what shall
we do now
and
on a case-by-case basis they got some of
those kids into their local community
college math programs
many of those kids went on to be very
successful
and now there's a 50-year follow-up of
those kids
and it turns out
if
these kids were in the top one percent
okay so everybody in this study is in
the top one percent if you take that
group
that rarefied group and divide them into
quartiles
so that you have the top 25 percent of
the top one percent and the bottom 25
percent
of the top one percent
you can find
on measurable
variables of success
the top quartile does better than the
bottom quartile in the top one percent
they have more patents they have more
publications they have more tenure at
universities and this is based on
their you're dividing them based on
their score at age 12.
i wonder how much interesting
data is in the variability in the
differences so but that that's really
that that's
oh boy that's very interesting but it's
also
i don't know somehow painful i don't
know why it's so painful
that that's so that g factor so
determinant
of even at in the nuanced
topic it's interesting that you find
that painful do you find it painful that
people with charisma
are very successful can be very
successful in life even though having no
other attributes other than they're
they're famous and people like them do
you feel that painful
yes if that charisma is untrainable
so one of the things again this is like
i learned psychology from the johnny
depp trial
but
one of the things the psychologist the
personality psychologist he could maybe
speak to this because he had interest
in this for time
is uh she was saying that personality
technically speaking is the thing that
doesn't change
over a lifetime it's the it's the thing
you're i don't know if she was actually
implying that you're born with it well
it's a trait it's a trait that's right
that's relatively stable over time that
i think that's generally correct so to
the degree your personality is stable
over time
yes that too
is painful
because what's not painful is the thing
you know
if i'm fat and out of shape i can
exercise
and
you know uh become healthier in that way
if my diet is a giant mess
and that's resulting in some kind of uh
conditions that my body is experiencing
i can fix that by having a better diet
that sort of my actions
my willed actions can make a change
if charisma is part of the personality
that's
the part of the charisma that is part of
the personality that is stable
yeah yeah that's painful too because
it's like oh i'm stuck with this
i'm stuck with this
well i mean and this pretty much
generalizes to every aspect of your
being this is who you are you've got to
deal with it and what it undermines of
course is a realistic appreciation for
this
undermines
the fairly recent
idea
prevalent in this country that if you
work hard you can be anything you want
to be
which has morphed from the original idea
that if you work hard you can be
successful
those are two different things yeah
and now we have
if you work hard you can be anything you
want to be
this is completely unrealistic i'm sorry
it just is now you can work hard and be
successful there's no question
but you know what the heart i could work
very hard and i am not going to be a
successful
uh theoretical physicist i'm just not
that said i mean we should
because we had this conversation already
but it's good to repeat
the fact that you're not going to be a
theoretical physicist
is not judgment on your basic humanity
returning again to the all men
which means men and women are created
equal
so again some of the differences we're
talking about in quote-unquote success
wealth
uh
number of uh whether you win a nobel
prize or not that doesn't um
put a measure on your basic humanity and
the
basic value
and even goodness of you as a human
being
because that
your basic role and value in society is
largely
within your control
uh it's it's some of these measures that
we're talking about
uh it's good it's good to remember this
um
one question about the flynn effect
what is it are humans getting smarter
over the years over the decades over the
centuries
the flint effect is james flynn who
passed away
about a year ago
published a
a set of analyses
going back a couple of decades
when he first noticed this that iq
scores
when you looked uh over the years seemed
to be drifting up
now this was not unknown to the people
who
make the test
because they renormed the test
periodically and they have to renorm the
test periodically because what
10 items correct
meant relative to other people
50 years ago is not the same as what 10
items mean relative
today
people are getting more things correct
now the scores have been drifting up
about three points iq scores have been
drifting up about three points per
decade this is not a personal effect
this is a cohort effect
well it's not for an individual
but the world what how do you explain so
what's that and this has presented
intelligence researchers with a great
mystery
two questions
first is it effect
on the fifty percent of the variance
that's the g factor or on the other
fifty percent
and there's evidence that it is a g
factor effect
and second what on earth causes this and
doesn't this mean intelligence and g
factor cannot be genetic
because the scale of natural selection
is
much much longer
than a couple of decades ago
and so it's been used
to try to undermine the idea that there
can be a genetic influence on
intelligence
but certainly it can be
the flint effect can affect the
non-genetic aspects of intelligence
because genes account for maybe 50
of the variance
may be higher it could be as high as 80
percent for adults but let's just say 50
percent for discussion
um
so the the flint effect is it's still a
mystery
it's still in this shape it's still a
mystery although the evidence is coming
out i told you before i edit a journal
on intelligence and we're doing a
special issue in honor of james flynn so
i'm starting to see papers now on the
really the latest research on this
um
i think most people who specialize in
this area of trying to understand the
flint effect
uh are coming to the
view based on data
that it has to do with advances in
nutrition and health care
and there's also evidence
that the effect is slowing down and
possibly reversing
oh boy so how would nutrition so
nutrition would still be connected to
the
g factor so nutrition as it relates to
the g factor so the biology that leads
to the intelligence
yes that would be the claim like
uh the the the hypothesis
being tested by the research yes and
there's some evidence from from infants
um
that nutrition has has made a difference
and so it's not an unreasonable
connection
but does it negate the idea that there's
a genetic influence not logically at all
so but it is very interesting so that if
you
take an iq test today
but you normal but you take the score
and use the tables that were available
in 1940
you're going to wind up with a much
higher iq number
so are we really
smarter than a couple of generations ago
no but
we might be able to solve problems a
little better
and make use of our rg because of things
like sesame street
and other curricula in school more
people are going to to to to school
uh so there are a lot of factors here to
disentangle
it it's fascinating though it's
fascinating that there's not clear
answers yet
that
as a population we're getting smarter we
just zoom out that's what it looks like
as a population getting smarter it's
interesting to see what the effects of
that are i mean this raises the question
we've mentioned it many times but
haven't clearly addressed it which is
nature versus nurture questions so
how much of intelligence is nature how
much of it is nurture how much of it is
determined by genetics versus
environment all of it
all of it is genetics no
all of it
is nature and nurture
yeah so yes
yes
okay uh
how much of the variance can you
apportion to either yeah most of the
people who work in this field say that
that is a the framing of that
if if the question is framed that way it
can't can't be answered because nature
and nurture are not two independent
influences
they interact with each other and
understanding those interactions
is so complex
that many behavioral geneticists say it
it is today impossible and always will
be impossible to disentangle that no
matter what kind of advances there are
in dna technology and genomic informatic
informatics but they're still to push
back on that
that same intuition from behavioral
geneticists
would lead me to believe that there
cannot possibly be a stable g factor
because it's super complex
many of them would assert that
as a logical outcome
[Music]
but because i believe there is a stable
g vector from lots of sources of data
not just one study but lots of sources
of data over decades
i am more
amenable to the idea
that whatever interactions between genes
and environment exist
they can be explicated
they can be
studied
and they
that information can be used as a basis
for molecular biology of intelligence
yes so and we'll do this exact question
because is it doesn't
the stability
of the g factor
give you at least a hint that there is a
biological basis for intelligence yes i
i think it's clear
that the fact that
an iq score is correlated to things like
thickness of your cortex
that is correlated to
glucose metabolic
rate in in your brain
that
identical twins reared apart
are highly similar in their iq scores
these are all
important observations
that certainly more than that indicate
not just suggest but indicate
that there's a biological basis and does
anyone believe intelligence has nothing
to do with the brain
i mean it's so obvious
well
indirectly definitely has to do with it
but the question is
environment interacting with the brain
or is it the actual
raw
hardware of the brain
well some would say
that the raw hardware of the brain
as it develops
from conception
through adulthood or at least through
the childhood
that that that so-called hardware that
you are assuming is mostly genetic
in fact
is not as deterministic as you might
think that it is probabilistic and what
affects the probabilities are things
like in uterine environment
and other factors like that including
chance
that chance
affects the way the neurons are
connecting during gestation
it's not
hey
it's pre-programmed
so there's there is
pushback on the concept that genes
provide a blueprint
that is a lot more fluid well but also
yeah so there's a lot a lot a lot
happens in the first few
months
of development
uh
so for in in nine months
in inside the mother's body and in the
uh
in and
you know the the months the few months
afterwards there's a lot of fascinating
stuff like including chance and luck
like you said
how things connect up
man the question is
afterwards the neuroplasticity of the
brain how much adjustment there is
relative to the environment how much
that affects the g factor but that's
where the
the whole conclusions of the studies
that we've been talking about is
that seems to have less and less and
less of an effect
as uh
pretty quickly
as yes and i do think there is more of a
genetic
by my view
and i'm not an expert on this i mean
genetics is a highly technical and
complex subject i am not a geneticist
not a behavioral geneticist but but
my reading of this my interpretation of
this is that
there is a genetic blueprint more or
less
and that has a profound influence on
your subsequent
intellectual development including the g
factor
and
that's not to say things can't happen
to i mean if you think of
that genes provide a potential
fine
and that various variables impact that
potential
and every parent of a newborn
implicitly or explicitly
wants to maximize that potential
this is why you buy educational toys
this is why you pay attention to organic
baby food this is why you do all these
things
because you want your baby to be as
healthy and as smart as possible and
every parent will say that
is there a case to be made can you steel
man the case
that
genetics
has
is a very tiny component of all this and
the environment is essential i don't
think the data supports that genetics is
a tiny component i think the data
support the idea that the genetics is a
very important and i don't say component
i say influence
very important influence
and the environment is a lot less than
people believe
most people believe environment plays a
big role
i'm not so sure guess what i'm asking
you is can you see where
what you just said it might be wrong
can you can you imagine a world
and what kind of evidence
would you need to see
to say you know what the intuition the
studies so far like reversing the
directions so one of the cool things we
have now more and more is we're getting
more and more data and the the rate of
the data is
is is escalating because of the digital
world so
when you start to look at a very large
scale of data
both on the biology side and the social
side we might be discovering some very
counterintuitive things about society we
might see the edge cases
that reveal that if we actually scale
those edge cases and they become like
the norm that will have a complete shift
in our
like you'll see
g factor be able to be modified
throughout life
in the teens and in the in in later life
so
a is in any case you can make or for
well your current intuitions are wrong
yes and it's a good question because i
think everyone should always be asked
what evidence would change your mind
yeah
uh it's certainly not only a fair
question it is really the key question
for anybody working on any aspect of
science
i think that if environment
was very important
we would have seen it clearly by now it
would have been obvious that school
interventions compensatory education
early childhood education all these
things that have been earnestly tried in
well-funded well-designed studies which
show some effect and they don't they
don't what what if the school the way
we've tried school compensatory school
sucks and when you what everybody said
at the beginning that's what everybody
said to jensen he said well maybe these
maybe we need to start earlier maybe we
need not do uh pre-kindergarten but
pre-pre-kindergarten yeah it's always an
infinite
well maybe we didn't get it right but
after decades of trying 50 years 50 or
60 years of trying
surely something
would have worked to the point where you
could actually see a result
and not need a
a probability level at .05 on some means
so that's why i
that's the kind of evidence
that would change my mind
population level
interventions like schooling that you
would you would see
um like this actually has an effect yes
and when you take adopted kids
and they grow up in a another family and
you find out when those adopted kids are
adults their iq scores don't correlate
with the iq scores of their adoptive
parents but they do correlate with their
iq scores of their biological parents
who whom they've never met
i mean these are important these are
powerful observations and it would be
convincing to you if
the reverse was true yes that would be
more now and there is
some data on adoption that indicates
that the adopted children are moving a
little bit more toward
their their adoptive parents
but it's you know it it's
to me the overwhelming the way i have
this concept called the weight of
evidence
where i don't interpret any one study
too much
the weight of evidence tells me genes
are important but what does that mean
what does it mean that genes are
important knowing that gene expression
genes don't express themselves in a
vacuum they express themselves in
an environment so the environment has to
have something to do with it especially
if the best genetic
estimates of the amount of variants that
are around 50 or even eight even if it's
as high as 80 percent it still leaves 20
percent
of non-genetic now maybe that is all uh
luck
maybe that's all chance i could believe
that i could easily believe that
so um
but i i do think
after 50 years of trying various
interventions
and nothing works including memory
training including listening to mozart
including playing computer games none of
that has shown any impact on
intelligence test scores is there data
on the intelligence the iq
of parents
as it relates to the children yes and
there is some evident genetic evidence
of kind of
of
of an interaction
between the parents iq and the
environment that high iq parents provide
an enriched environment
which then can
impact the child in addition to the
genes it's that
environment so there are all these
interactions that you know um
but it's not you know
think about the number of books in a
household this was a variable that's
correlated with iq
and and uh it is yeah well well why
especially if the kid never reads any of
the books it's because
more intelligent people
have more books in their house
and if you're more intelligent
and there's a genetic component to that
the child will get those genes or some
of those genes as well as as the
environment but it's not the number of
books in the house that
actually directly impacts the child so
the two scenarios on this are you find
that
and this was used to
get rid of the s.a.t test oh the sat
scores highly correlated with the social
economic status of the parents so all
you're really measuring is how rich the
parents are
okay well why are the parents rich
yes
and so you could the opposite
kind of
uh syllogism is that
people who are very bright make more
money
they can afford
homes in in better neighborhoods so
their kids get better schools now the
kids grow up bright
where in that chain of events does that
come from
well unless you have a genetically
informative research design
where you look at siblings that have the
same biological parents and
and so on you can't really disentangle
all that
most studies of social economic status
and intelligence
do not have a genetically informed
design so any conclusions they make
about the causality of the social
economic status being the cause of the
iq
is is a stretch
and where you do find genetically
informative designs
you find most of the variants in your
outcome measures
are
due to the genetic component and
sometimes the ses adds a little
but uh
the weight of evidence is it doesn't add
very much variance to predict what's
going on beyond
the genetic variance
so when you actually look at it in in in
some and there aren't that many studies
that have genetically informed designs
uh but when you you do see those the
genes seem to have an advantage sorry
for the strange questions but there's is
there a connection
[Music]
um
fertility or the number of kids that you
have
and g factor so you know the kind of
conventional wisdom is
people of
maybe is it higher economic status or
something like that or having fewer
children
i just loosely hear these kinds of
things is there is there data are that
you're aware of in one direction or
another on this
well
strange questions always get strange
answers
yes right uh
yeah do you have a strange answer for
that stranger the answer is there used
to
there were some studies that indicated
the more children
in a family
the the firstborn children would be more
intelligent than the fourth or fifth or
sixth
it's not clear that those studies
hold up
over time and of course what you see
also
is that
families where there are
multiple children four five six seven
you know really big families
uh
the social economic status of those
families usually in the modern age is
not that high
uh it maybe it used to be the
aristocracy used to have a lot of kids
i'm not sure exactly but there there
there have been reports uh
of uh
correlations between iq and fertility
um but i'm not sure that the data are
very strong that the firstborn
child is always the smartest it seems
like there's some data to that but i'm
not current on that
how would that be explained that would
be an uh a nurture
well it could be nurture it could be in
uterine environment i mean boy the
biology is complicated
and this is why this you know
like many areas of science you you said
earlier that there are a lot of gray
areas and
no definitive answers
this is not uncommon in science that the
closer you look
at a problem
the more questions you get not the fewer
questions
because the universe is complicated
and the idea that we have people on this
planet
who can study the first nanoseconds of
the big bang
that's pretty amazing
and i've always said that if they can
study the first
nanoseconds of the big bang we can
certainly figure out something about
intelligence
that allows that
i'm not sure what's more complicated the
human mind or the physics of the
universe
uh it's unclear to me
i think we over
a very humbling statement
maybe it's very human-centric
egotistical statement that our mind is
somehow super complicated but biology is
a tricky one to
unravel consciousness
what is that well i i've always believed
that consciousness and intelligence are
the two
real
fundamental problems of the human brain
and i and i and therefore i think they
must be related
uh yeah and heart problems like uh walk
together holding hands kind of kind of
kind of idea you may not know this but i
i did some of the early research on
anesthetic drugs with brain imaging
trying to answer the question what part
of the brain is the last to turn off
when someone loses consciousness
and is that the first part of the brain
to turn on
when consciousness is regained
and i was working with an
anesthesiologist named mike alkire who
was really brilliant at this these were
really the first studies of brain
imaging uh using positron emission
tomography
long before uh fmri
and you would inject a radioactive sugar
that labeled the brain and the harder
the brain was working the more sugar it
would take up and then you could make a
picture of
glucose use in the brain and we
he he was amazing he managed to do this
in normal volunteers he brought in
and anesthetized as if they were going
into surgery
and he managed all the human subjects
requirements on this research
and uh it was he was brilliant at this
and
what we did is we had these normal
volunteers come in on three occasions
on one occasion he gave them enough
anesthetic drug
so they were
a little drowsy
and on another occasion they came in and
he fully anesthetized them
and you know he would say
you know
mike can you can you hear me
and the person would say uh
yeah
you know that's him and then
that we would scan people under the and
under uh
no anesthetic condition so same person
and um we were looking to see if we
could see
the part of the brain
turn off
you subsequently tried to do this with
fmri which has a faster time resolution
and you could do it in real time as the
person went under and then regained
consciousness where you couldn't do that
with pet you had to have three test
and
the results were absolutely fascinating
we did this with different anesthetic
drugs
and different drugs impacted different
parts of the brain so we were naturally
looking for the common
and it seemed to have something to do
with the thalamus
and consciousness this was actual data
unconsciousness
real con actual consciousness what part
of the brain turns on uh what part of
the brain turns off
it's not so clear
but maybe has something to do with the
thelma the the the sequence of events
seem to have the thalamus in it boy um
now here's the question
are some people more conscious than
others
are there individual differences in
consciousness
and i don't mean it in the um
psychedelic sense i don't mean it in the
political consciousness sense i just
mean it in everyday life to some people
go through everyday life more conscious
than others and are those the people we
might actually label more intelligent
so now the other thing i was looking for
is whether the parts of the brain we
were seeing in the anesthesia studies
were the same parts of the brain we were
seeing in the intelligence studies
now this is you know this was very
complicated expensive research we didn't
really have funding to do this we were
trying to do it on the fly i'm not sure
anybody has pursued this you know i i'm
retired now uh he's gone on to other
things
but it's i think it's an area of
research that that would be fascinating
to see
the parts and there are a lot more
imaging studies now of consciousness i'm
just not up on them so but basically the
question is which imaging so newer
imaging studies
to see
in high resolution spatial and temporal
way which part of the brain lights up
uh when you're doing intelligence tasks
and which parts of the brain lights up
when you're doing consciousness tasks
and see the interplay between them you
try to infer that's the challenge of
neuroscience
without understanding deeply
looking from the outside try to infer
something about
uh how the whole thing works
well imagine this here's a simple
question
does it take more anesthetic drug
to put
to to have a person lose consciousness
consciousness if their iq is 140
then a person with an iq of 70.
that's an interesting way to study it
yeah i mean if there is if there is
a yeah if the answer to that this is a
stable yes that's very interesting so i
tried to find out
and i went to some anesthesiology
textbooks about how you you dose
and they dose by weight
and
what i also learned this is a
little bit off subject
anesthesiologists
are never sure if you how deep you are
yeah and they usually
tell by poking you with a needle and if
you don't jump they tell the surgeon to
go ahead
i'm not sure that's
literally true but it's
well it might be very difficult to know
precisely
how deep you are it has to do with the
same kind of measurements that you're
doing with the consciousness with the
it's
it's it's difficult it's difficult to
know so i don't lose my train of thought
i couldn't find in the textbooks
anything about dosing by intelligence
i asked my friend the anesthesiologist
he said no he doesn't know i said can we
do a chart review
and look at people using their years of
education as a proxy for iq
because if someone's gone to graduate
school that tells you something you can
make some inference as opposed to
someone who didn't graduate high school
you know can we do a chart review and he
says no they they never really put down
the the exact dose and no he said no so
to this day that the the the the simple
question does it take more anesthetic
drug
to put someone under if they have a high
iq
or less
or less it could go either way because
by the way our early pet scan studies of
intelligence
found
the
unexpected result of an inverse
correlation between glucose metabolic
rate and intelligence it wasn't how much
a brain area lit up
how much it lit up was negatively
correlated to how well they did on the
test which led to the brain efficiency
hypothesis which is still being studied
today
and
there's more and more evidence that the
efficiency of brain information
processing is more related to
intelligence than
than
just more activity yeah and it'll be
interesting again that's the total
hypothesis how much in the relationship
between intelligence and consciousness
it's not obvious that those two if
there's correlation that would be
uh
they could be inversely correlated
wouldn't that be funny
if you uh
the
the consciousness factor the c factor
plus the g factor equals one
it's a nice trade-off
you get you get you get a trade-off how
deeply you experience the world versus
how
deeply you're able to
reason through the world what a great
hypothesis
certainly somebody listening to this can
do this study even if it's the aliens
analyzing humans uh a few centuries from
now let me ask you from an ai
perspective
um
i don't know how much you've thought
about machines
but and you know there's the famous
touring test test of intelligence for
machines
um which is a beautiful
almost like uh cute formulation of
intelligence
that
alan turing proposed basically
conversation being if you can fool a
human to think
that
a machine is is a human that passes the
test i suppose you could do a similar
thing
um
for humans
if i can fool you that i'm intelligent
then that's a good test of intelligence
right
like uh you're you're talking to two
people
and
my
your your your the test is saying
who has a higher iq
and uh it's an interesting test because
yeah maybe charisma can be very useful
there uh and you're only allowed to use
conversation which is the formulation of
the turing test anyway all that to say
is what are good tests of intelligence
for machines
you know we uh what do you think it
takes to achieve human level
intelligence for machines
well i have thought a little bit about
this but you know i
every time i i think about these things
i rapidly reach the
limits of my
knowledge and and imagination
so when um
alexa first came out
and i i think um
there was a a competing one well there
was siri with apple and google had alexa
no no uh amazon had alexa yeah amazon
had a lot of google
assistant something so i i proposed to
one of my colleagues that
he buy one of these each you know one of
each
and then
ask it questions from the iq test
yes
but
it became apparent that
they all searched the internet
so they all can find answers to
questions like how far is it between
washington and miami
and repeat after me now i don't know if
you said to uh alexa
i'm going to uh re repeat these numbers
backwards to me
i don't know what would happen i've
never done it
but the the so so one answer to your
question is try you're going to try it
right now let's try it
let's try it no yes sir
so i i it would actually probably go to
google search and it will be all
confusing kind of stuff
it would uh it would fail well then i
guess that there's a test that that it
would fail
well but that's not that has to do more
with the
you know uh
the language of communication versus the
content so if you did an iq test to a
person who doesn't speak english and the
test was administered in english that's
not really the test of well let's think
about the computers that beat the
jeopardy champions
yeah so that so that
because i happen to know how those are
programs are very hard-coded and there's
definitely a lack of intelligence there
there's
uh something like
iq tests uh there's a there's a guy
uh artificial intelligence researcher uh
francois chole he's he's a google he's
one of the
seminal people in machine learning he
also as a fun aside thing
uh develop an iq test for machines oh
i'll actually email you this because it
would be very interesting for you it
doesn't get much attention because
people don't know what to do with it
uh but it deserves a lot of attention
which is it basically does a pattern
type of tests
where you have to do uh you know one
standard one is
you're given three things and you have
to do a fourth one that that kind of
thing you have to understand the pattern
here and for that it really simplifies
to um
so the interesting thing is
he's trying not to achieve high iq he's
trying to achieve like pretty
low bar for iq
things that are kind of trivial for
humans
and they're actually really tough for
machines which is seeing
playing with these concepts of
symmetry of counting like if i give you
one object two objects three objects
you'll know the the the last one is four
objects you can like count them you can
you can cluster objects together it's
both visually and conceptually we could
do all these things with our mind that
we take for granted
the object-ness of things we can like
figure out what uh
spatially is an object and isn't
and we can play with those ideas um
and machines
really struggle with that so he really
cleanly formulated these iq tests i
wonder what like
uh that would equate to for humans with
iq but it'd be a very low iq
uh but that's exactly the kind of
formulation like okay we want to be able
to solve this how do we solve this and
he does it as a challenge and nobody's
been able to um it's similar to the
alexa prize which is amazon is hosting a
conversational challenge uh nobody's
been able to do well on on his but
that's an interesting
uh those kinds of tests are interesting
because we we take for granted
all the
the ability of the human mind
to play with concepts and
to
formulate concepts out of novel things
so like things we've never seen before
we were able to
use that i mean that's
i've talked to a few people that design
iq tests sort of online they write iq
tests
and i was trying to get some questions
from them and they they spoke to the
fact that we can't really share
questions with you because
part of the
um
like first of all it's really hard work
to come up with questions
like it's really really hard work it
takes a lot it takes a lot of research
but it also takes a lot you it's novelty
generating you're you're
constantly coming up with really new
things
and
um part of the point is that you're not
they're not supposed to be public that
they're supposed to be new to you when
you look at them
it's interesting that the novelty is
fundamental to the hardness of the
problem
at least a part of what makes the
problem hard is you've never seen it
before right that's called fluid
intelligence as opposed to what's called
crystallized intelligence which is your
knowledge of of facts
you know things
but can you use those things to solve a
problem those are two different things
do you think we'll be able to
because we spoke and i don't want to
miss uh opportunity to talk about this
we spoke about the neurobiology about
the molecular biology of intelligence do
you think one day we'll be able to
modify the biology
of uh or the genetics of a person
to uh
uh modify their intelligence decrease
their intelligence we started this
conversation by talking about a pill you
could take do you think that such a pill
would exist metaphorically i do
and i am supremely confident that it's
possible because i am supremely ignorant
of the complexities of neurobiology
and so i have written ignorance is bliss
well i have written that the nightmares
of neurobiologists
you know understanding the complexities
this cascade of events that happens
at the synaptic level
that these nightmares are what fuel some
people to solve
so some people
you have to be undaunted i mean yeah
this is this is not easy
look we're still trying to figure out
cancer
yeah
it was only recently that they figured
out why aspirin works
you know i these are not easy problems
but i also have the perspective
of
the history of science
is the history of solving
problems
that are
extraordinarily complex
and seem impossible and seem impossible
at the time and so one of the
things you look at at companies like
neurolink
you have brain computer interfaces
you start to delve into the human mind
and start to talk about machines
measuring but also sending signals to
the human mind you start to wonder
what that
has uh what impact that has on
the g factor
modifying in small ways or in large ways
the functioning
the uh
the mechanical electrical
of chemical functioning of the brain
i
look at everything about the brain there
are different levels of explanation on
one hand you have a behavioral level
but then you have brain circuitry
and then you have
neurons
and then you have dendrites
and then you have synapses
and and then you have
the the neurotransmitters
and the presynaptic and the postsynaptic
terminals
and then you have all the things that
influence
neurotransmitters
and then you have
the individual differences among people
yeah it's complicated
but 51
million people in the united states
have iqs under 85
and struggle
with everyday life
shouldn't that motivate
people to take a look at this yeah
you know
yeah
now but i just want to linger one more
time that um
you have to remember that the science of
intelligence
the measure of intelligence
is only a part of the human condition
the thing that makes life beautiful and
the creation of beautiful things in this
world
is is uh
perhaps
loosely correlated
but is not dependent entirely on
intelligence
absolutely i i certainly agree with that
that's so
for anyone sort of uh
listening i'm still not convinced
that um
sort of
more intelligence is always better if
you want to create beauty in this world
i don't know well i didn't say more
intelligence is always better if you
want to create beauty i just said
all things being equal more is better
than less
that's all i mean yeah but that's sort
of that i just want to sort of say
because a lot to me
one of the things that
makes life great is the opportunity to
create beautiful things and and so i
just want to sort of empower people to
to do that no matter what
some iq test says
at the population level we do need to
look at iq tests to help to help people
and to also inspire us yeah to do to
take on some of these extremely
difficult scientific scientific
questions
do you have advice
for young people
in high school in college
whether they're thinking about career or
they're thinking about a life they can
be proud of is there advice you can give
whether they're in the
they want to pursue psychology or
biology or engineering or they want to
be artists and musicians and poets
i i can't advise anybody on that level
of what
their passion is
uh
you know but i i can't say if you're
interested in psychology if you're
interested in science
and the science
uh around
the big questions of consciousness and
intelligence
and psychiatric illness
we haven't really talked about brain
illnesses
and what we might learn from uh you know
if you are trying to develop a drug to
treat alzheimer's disease you are trying
to develop a drug
to impact learning and memory
which are core to intelligence
so it could well be that the so-called
iq pill will come from a pharmaceutical
company trying to develop a drug for
alzheimer's disease because that's
exactly what you're trying to do right
yeah well
what will that what will that drug do in
a college student that doesn't have
alzheimer's disease
so
i would encourage
people who are interested in psychology
who are interested in science
to pursue a scientific
career
and address the big questions and this
you and the the the the most important
thing i can tell you if you're going to
be in kind of a a research environment
is you got to follow the data where the
data take you you can't decide in
advance where you want the data to go
and if the data take you to places that
you don't have the technical expertise
to follow
like you know i would like to to
understand more about molecular biology
but i'm not going to become a molecular
biologist now but i know people who are
and my job is to get them interested to
take their expertise into this direction
and that it's not so easy but uh and if
the data takes you to a place
that's controversial that's
counterintuitive in this world
um
no
i would say
it's probably a good idea to still push
forward boldly
but to communicate the
interpretation of the results with skill
with compassion
with uh with with a greater breadth of
understanding
of humanity not just the science
of the impact of the results one famous
psychologist wrote about this issue that
somehow a balance has to be found
between pursuing the science and
communicating it with respect to
people's sensitivities the legitimate
sensitivities
somehow
he didn't say how
somehow somehow and this is part of that
sentence somehow and balance
is left up to the interpretation of the
reader
let me ask you said big questions the
biggest
or one of the biggest
we already talked about consciousness
and intelligence one of the most
fascinating one of the biggest questions
but let's talk about the why
why are we here
what's the meaning of life
oh i'm not going to tell you
you know you're not going to tell me
this is very
i'm going to have to wait for your next
book
the meaning of life you know
uh
we do the best we can to get through the
day
and and then there's just a finite
number of the days
are you uh are you afraid the finiteness
of it do you think i think about it more
and more as i get older
yeah i i do uh
and it's one of these human things that
it is finite we all know it
um
most of us deny it
uh and don't want to think about it
sometimes you you think about it in
terms of estate planning you try to do
the rational thing right sometimes you
it makes you work harder because you
know your time is more and more limited
and you want to get things done
i don't know where i am on that
uh it is uh
uh just one of those things that's
always in the back of my mind
it's as i don't think that's uncommon
well it's just like g factor
intelligence it's a hard truth that's
there
and sometimes you kind of
walk past it and you don't want to look
at it
but it's still there yeah
yes you can't escape it
and
think about the g factor in intelligence
is everybody
knows this is true on a personal daily
basis
you if even if you think back to when
you were in school
you know who the smart kids were
you know
when you are on the phone talking to a
customer service representative that in
response to your detailed question is
reading a script
back to you and you get furious at this
and you and have you ever called this
person a or wanted to call this
person a you're not listening to
me everybody has had the experience of
dealing with people who they think are
not at their level
it's it's just common because that's the
way human beings are that's the way life
is but we also we also
have a poor estimation of our own
intelligence we have a poor and we're
not always a great this
our judgment of human character of other
people is not as good
as a battery of tests
we there's there's there's
that's where bias comes in
that's where
our history our emotions all of that
comes in so you know people on the
internet you know there's such a thing
as the internet
and people on the internet will call
each other dumb all the time and um
you know i
that's the worry here is that
um we give up on people
we put them in a bin
just because of one interaction or
some small number of interactions as if
that's it they're hopeless that's just
in their genetics but
i i think no matter what the science
here says
once again
that does not mean we should not have
compassion for our fellow man
that's exactly what the science does say
it's not it's not
opposite of what the science is
everything i know about psychology
everything i've learned about
intelligence
everything
points to the inexorable conclusion that
you have to treat treat people
as individuals respectfully and with
compassion because through no fault of
their own some people are not as capable
as others
and you want to turn a blind eye to it
you want to come up with with
theories about why that might be true
fine i would like to fix some of it
as best i can
and everybody
is uh deserving of love
richard this is a good way to end it i
think um i think he's getting warmed up
here i know um
i know you can go for another many hours
but uh
and to respect your extremely valuable
time this is an amazing conversation
thank you for
um
for the teaching company the the
lectures you've given uh with the
neuroscience of intelligence just the
work you're doing it's a it's a
difficult topic
it's a topic that's controversial and
sensitive to people and to push forward
boldly
and in that nuanced way just thank you
for everything you do and thank you for
asking the big questions of intelligence
of consciousness well thank you for
asking me i mean there's nothing like
good conversation on these topics
thanks for listening to this
conversation with richard heyer to
support this podcast please check out
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and now let me leave you with some words
from albert einstein
it is not that i'm so smart
but i stay with the questions much
longer thank you for listening and hope
to see you next time