How can you change someone's mind? (hint: facts aren't always enough) - Hugo Mercier
Three people are at a dinner party.
Paul, who’s married, is looking at Linda.
Meanwhile, Linda is looking at John,
who’s not married.
Is someone who’s married looking
at someone who’s not married?
Take a moment to think about it.
Most people answer that there’s
not enough information to tell.
And most people are wrong.
Linda must be either married
or not married—there are no other options.
So in either scenario, someone married
is looking at someone who’s not married.
When presented with the explanation,
most people change their minds
and accept the correct answer,
despite being very confident
in their first responses.
Now let’s look at another case.
A 2005 study by Brendan Nyhan
and Jason Reifler
examined American attitudes regarding
the justifications for the Iraq War.
Researchers presented participants
with a news article
that showed no weapons
of mass destruction had been found.
Yet many participants not only continued
to believe that WMDs had been found,
but they even became more convinced
of their original views.
So why do arguments change people’s minds
in some cases and backfire in others?
Arguments are more convincing when they
rest on a good knowledge of the audience,
taking into account
what the audience believes,
who they trust,
and what they value.
Mathematical and logical arguments
like the dinner party brainteaser work
because even when people
reach different conclusions,
they’re starting from
the same set of shared beliefs.
In 1931, a young, unknown mathematician
named Kurt Gödel presented a proof
that a logically complete
system of mathematics was impossible.
Despite upending decades of
work by brilliant mathematicians
like Bertrand Russell and David Hilbert,
the proof was accepted
because it relied on axioms that
everyone in the field already agreed on.
Of course, many disagreements involve
different beliefs
that can’t simply be reconciled
through logic.
When these beliefs involve
outside information,
the issue often comes down to
what sources and authorities people trust.
One study asked people to estimate
several statistics
related to the scope of climate change.
Participants were asked questions,
such as “how many of the years
between 1995 and 2006
were one of the hottest 12 years
since 1850?”
After providing their answers,
they were presented with data from the
Intergovernmental Panel on Climate Change,
in this case showing that the answer
was 11 of the 12 years.
Being provided with these reliable
statistics from a trusted official source
made people more likely to accept
the reality that the earth is warming.
Finally, for disagreements that
can’t be definitively settled
with statistics or evidence,
making a convincing argument
may depend on engaging
the audience’s values.
For example, researchers have conducted
a number of studies
where they’ve asked people
of different political backgrounds
to rank their values.
Liberals in these studies,
on average, rank fairness—
here meaning whether everyone is treated
in the same way—above loyalty.
In later studies, researchers attempted
to convince liberals
to support military spending with
a variety of arguments.
Arguments based on fairness—
like that the military provides employment
and education to people
from disadvantaged backgrounds—
were more convincing than arguments
based on loyalty—
such as that the military
unifies a nation.
These three elements—
beliefs, trusted sources, and values—
may seem like a simple formula
for finding agreement and consensus.
The problem is that our initial
inclination is to think of arguments
that rely on our own beliefs,
trusted sources, and values.
And even when we don’t,
it can be challenging to correctly
identify what’s held dear
by people who don’t already agree with us.
The best way to find out
is simply to talk to them.
In the course of discussion,
you’ll be exposed to counter-arguments
and rebuttals.
These can help you make your own
arguments and reasoning more convincing
and sometimes, you may even end up
being the one changing your mind.
