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 progra