universe
back in the 1950s Princeton and
Dartmouth the students of these two
universities saw a football game rather
they saw two different games in one game
the Dartmouth team played dirty they
tackle Princeton’s star quarterback well
after he had thrown a pass giving him a
concussion breaking his nose and taking
him out of the game in the other game it
was the Princeton players who were
playing dirty they injured one Dartmouth
players leg and broken others now these
two games were actually happening at the
same time and at the same place and with
the same players and referees actually
the only thing that made these two games
different was which team you happen to
be a fan of if you were a Princeton
student you thought the Dartmouth team
made twice as many infractions and the
infractions they did make were flagrant
and if you were a Dartmouth student you
thought that the two teams made about
the same number of infractions and the
Princeton students were exaggerating how
flagrant the infractions actually were
now what really happened in this game
isn’t all that important what’s more
important is what we can learn from it
despite seeing the exact same game the
two teams came to radically different
conclusions and it shouldn’t surprise
you now when I say that our political
arena is split in much the same way both
sides see the other as hateful malicious
and stupid and they see their own side
as righteous and rational and this
problem only seems have been getting
worse over the past couple decades in a
recent Pew survey of 10,000 Americans
they asked Democrats and Republicans how
favorably they view the other side in
1994 when this question was asked 16
percent of Democrats and 17 percent of
Republicans through the other side very
unfavorably in the most recent survey
these numbers have jumped up to 38
percent and 43 percent respectively
now one of the consequences of this
ideological divide that I found
especially interesting is how it affects
our understanding of science money
issues as diverse as evolution or
climate change or fracking or
genetically modified organisms we see
people people vehemently disagreeing
with each other and with the scientific
consensus before I move on though I want
to emphasize that this kind of
polarization is actually quite rare when
we get a bad infection or break a bone
we go to the doctor because we know
that’s the relevant expert to go to we
don’t form conspiracy theories about a
cabal of scientists trying to manipulate
our understanding of our health and
well-being and the same is true for any
number of scientific topics like how
long tortoises live or whether or not
Pluto is a planet or how to make a light
bulb for all these topics and more our
political ideology doesn’t affect how we
look for and interpret that information
it’s only on these rare issues like
climate change or GMOs where we see this
kind of polarization nonetheless the
fact that our political affiliations can
affect how we think about scientific
evidence should trouble us if we want to
build a world that’s open to the
discoveries of science we should worry
when we start thinking of science like a
football game with winners and losers
doesn’t matter what happened in a game
over half a century ago but it does
matter whether or not our earth is
warming it does matter whether or not
our foods are poisonous regardless of
your political orientation we can all
agree that the answers to these
questions matter where we disagree is in
what we think the answers are and in
some cases liberals diverge from the
scientific consensus and in others
conservatives do if we can understand
why this happens
perhaps we can change it so that all
Americans can come to a better
appreciation of the amazing insights
that science has to offer
now the problem isn’t that we don’t have
any explanations for why this
polarization occurs the problem is
actually that we have too many
explanations
that each have a ring of possibilities
to them so to disentangle one
explanation from another we have to turn
through the evidence so I’ll be talking
about two explanations today one
explanation is what’s been called the
public irrationality thesis and I think
the best work that’s been done on this
topic has been by Dan kahan at Yale
University and the idea behind the
public rationality thesis is that people
get things wrong about science because
they don’t think like scientists maybe
they’re less knowledgeable or like the
analytic or reflective kinds of mindsets
that scientists are known for and this
is what causes them to be uninformed or
easily misled by people who want to
manipulate them like I said this is a
plausible explanation but how might we
test it well if the public rationality
thesis were true
we might expect that as person became
more knowledgeable or better at
interpreting quantitative information
their beliefs would converge towards the
scientific consensus but this actually
isn’t what we find as a person becomes
better along these dimensions we
actually see greater polarization so on
a topic like climate change for example
conservatives will leave even more but
climate change doesn’t pose a risk to
humans and liberals will leave even more
that it does so this seems like an
anomaly for the public irrationality
thesis you can’t easily explain this
pattern of results but there is another
explanation it’s called the cultural
cognition thesis and the idea here is
that our beliefs might not just be
tracking the truth instead we might be
motivated to form our beliefs in a way
that signals our commitments to our
identities and to people with whom we
share relationship in short our culture
and as a person becomes more
knowledgeable or better at interpreting
quantitative information they’re better
at finding the evidence that fits their
worldviews so it’s like if one of those
Princeton students watching the game was
wearing binoculars they’d be much better
at seeing what was happening on the
field and much better at seeing all the
other team’s faults but at the same time
by wearing those binoculars they would
have been so intently focused on
whatever it is that they wanted to find
at the exclusion of everything else and
if you’re a Princeton student you’re
going to want to find all those times
when
the Dartmouth team is acting unfairly
and you’re going to want to find all the
excuses for your own team and so now to
return to the cultural cognition thesis
the reason why we see greater
polarization as people become more
scientifically literate or numerate is
because the world is complicated and
there’s always going to be mixed
evidence and we’re motivated to find the
evidence that fits with our worldviews
it’s just that the people who know more
and who are better at deliberative
reasoning are better at finding that
evidence this is a plausible and
evidence-based explanation for why
America is polarized or for issues that
should ordinarily be in the domain of
science
not politics it’s because we’re
motivated to be good members of our
group and because positions on certain
scientific topics come to be markers of
which group we belong to I want to
emphasize though that fitting your
observations to your worldviews isn’t
necessarily a bad thing in fact in some
cases it can make complete sense so if
you’re a Princeton student watching the
game it might not be in your best
interest to say actually guys our team
was acting a little aggressively that’s
how you lose friends and similarly when
you’re a conservative down in Texas it
might not be in your best interest to
say that you’re in favor of gun control
you might get suspicious glances people
might question your motives you might
get shunned or ostracized from your
group and the same might be true if
you’re against gun control in Virginia
Tech or Newton Massachusetts the sights
of two horrible mass shootings that
that’s what do you gain by adopting
these beliefs your individual voice
isn’t going to sway policies and you
aren’t going to live your day-to-day
life any differently as a result of
understanding of science behind gun
control going going to cook dinner
better and you aren’t going to watch
more entertaining TV shows all you
really gain is the satisfaction of
knowing that you’re right but
collectively when politicians Institute
policies that reflect the will of their
biased constituents ringette policies
that don’t reflect the consensus of
scientific experts and we can get
policies that
damage the lives of thousands if not
millions of people so how might we
change this well I’m not sure I have the
answers but I do know that this kind of
polarization isn’t inevitable in one of
the studies Dan Kahn conducted with his
colleagues he measured how curious
people were about science among other
things he asked people what kinds of
books they read and how often they went
to museums and public lectures and how
often they talk to their friends and
family about science and technology and
what he found was as people showed
greater curiosity in science the less
polarized they became what this suggests
is that other motivations besides our
desire to affiliate with our group can
affect how we perceive scientific facts
it turns out an appetite for surprise
and wonder can work to mitigate our
tendency to engage in biased reasoning
so stepping back now from the individual
level we can look at the cultural
meanings associated with position from
certain scientific topics in another
study Kahn conducted with his colleagues
he gave people an excerpt saying that
the effects of climate change would be
even more dire than scientists had
previously predicted but before doing so
he gave them a statement ostensibly
written by the American Association of
geophysical scientists either urging
even stricter restrictions on carbon
emissions or a statement calling for
greater investments in geoengineering as
an alternative to these carbon emission
restrictions when participants read the
statement on geoengineering we saw less
polarization and the conservative
participants were more willing to admit
the possibility that climate change
might actually pose a risk to humans
again the reason behind this is because
climate change took on a different
meaning for these participants
by appealing to geoengineering these
researchers appeal to the value that can
serve this place on overcoming nature’s
limits through commerce technology and
Industry and with its in mind the
accepting climate change became less of
a threat to these conservatives
identities and so their evaluation of
the evidence was less distorted by the
commitments to their cultural worldviews
so the broader point is that if you want
even a slim chance of changing a
person’s mind on some politically
contested scientific topic the first
step is to understand why people hold
the beliefs that they do it might not be
because they’re stupid but rather
because they’re smart it might be
because they know how to evaluate the
evidence consciously or not in a way
that affirms their commitments to their
cultural worldviews and so one way to
get this broader understanding is to
actually engage with people that you
disagree with and I don’t just mean
turning on Fox News or MSNBC I mean
actually talk with people have
cross-cutting conversations
conversations with people from across
the aisle you’ll improve your ability to
articulate the reasons why people hold
the beliefs that they do and who knows
you might even improve your
understanding of your own views along
and finally once you do understand the
people that you’re talking to use that
understanding to strip the issue of its
climate change and GMOs or any other
scientific topic doesn’t have to be a
liberal or conservative issue politics
is about how we as a nation should
respond to the way the world is but the
way the world is doesn’t care if you’re
a liberal or conservative the ocean will
rise or fall regardless of your
political ideology but like I said the
insights of science matter here both
liberals and conservatives have a stake
in knowing what the truth is so instead
of the win-lose kinds of conversations
that political pundits typically have an
emphasis on this cooperative pursuit of
the truth might work better it might be
more effective in changing people’s
minds so the science doesn’t have to be
a football game it’s more like a
three-legged race except instead of
everyone racing against each other
everyone’s legs are tied together and
while just struggling to get to the
finish line and so we have to coordinate
and cooperate with each other if we want
to move in the right direction and
realizing this is the first step towards
bridging the ideological divide and
building a more enlightened society
that’s able to take full advantage of the discoveries of science thank you