So, as Josh was just saying,
what's distinctive about human intelligence
is not just its speed or capacity,
but our ability to go beyond the visible statistics of our environment
to infer the hidden causes that explain what we see.
So only one of these pictures of wild flowers makes you infer
the presence of an invisible person.
And similarly, when we see something complicated or surprising,
the invisible cause we most often infer
is another person or at least another mind.
So think about crop circles or intelligent design or, my favorite,
an??? word that means
someone seen from a far off and blamed for otherwise
inexplicable circumstances.
So in a real sense human intelligence is intelligence about humans.
And correspondingly, if you look inside the brain of a human adult,
you find that in addition to the older brain regions that we share
with other animals and that we use for seeing, hearing, feeling,
and for controlling our movements,
humans also have another distinctive set of brain regions
that we’re only discovering now through modern or imaging technology,
and whose functions are specifically related to other people,
to recognizing their faces and voices,
seeing their actions and understanding their emotions.
And perhaps most surprisingly is the brain region I study,
a small brain region above and behind your right ear
called the right temporal-parietal junction or RTPJ for short,
whose function is specifically related to understanding other minds,
people’s thoughts, beliefs, desires, and intentions.
This data come from a group we call normal human adults.
They’re MIT undergraduates.
So this capacity to think about other people’s minds
is a distinctive feature of human intelligence
and it helps to explain why computers could beat human opponents at chess
so many years before they could beat them at poker
and why a human five-year old child would still beat a computer
at understanding the plot of Little Red Riding Hood.
Or to give you another example that’s maybe more --
World Economic Forum, compare what a computer does when it solves
the complex differential equation that describes a financial market
to what you do if you hear Alan Greenspan say,
"I know you think you understand what you thought I said,
"but I’m not sure you realize that what you heard was not what I meant."
So on all of these cases, the ability to understand another mind
is the glue that binds together our societies, our social relationships,
and our families, which is why its loss can be so devastating
to children with autism and their families.
So in minor research we’re designing experiments
that allow us to measure this human capacity.
For example, we tell people stories.
I’m gonna give you an example right now.
Grace is making a cup of coffee for her friend and next to the coffee
is a jar of a white powder which is just regular sugar.
But because the powder is labeled toxic poison,
Grace thinks the powder is toxic poison and she puts it in her friend’s coffee.
Was that morally permissible?
So, hopefully, you think no, and most adults, when we asked them,
say no, it wasn’t permissible, because she thought it was poison
even though it was really just sugar.
And while they’re making that judgment
we see activities specifically in this brain region and the amount of activity
in this brain region lets us predict which moral judgment they’ll make.
I’m also interested in how this brain region matures in childhood,
because if you ask similar questions to children, you get different answers.
Three-year olds and even five-year olds will tell you there’s nothing wrong
with what Grace did because nothing bad happened
and it’s not until children are seven that they start to give the adult-like answer
that it was wrong because she thought it was poison
even though nothing bad happened in the end.
And even in adults if we temporarily disrupt function in this brain region
by passing a magnetic pulse through their skull with the tool called
transcranial magnetic stimulation,
we can temporarily change the moral judgments that they make
making them more like the younger children shifting attention away from
Grace’s thoughts and intentions and towards the actual consequences.
So recently I’ve also been interested in how similar processes happen
outside the lab.
How we use our RTPJ to decide who’s honest or dishonest,
who to blame and who to forgive or when something bad happens,
who was responsible based on what they knew and when they knew it.
I’m also interested in how we use the same systems
to make decisions about our own actions.
I mean, just recent research in psychology suggests that when people
are deciding whether to cheat or whether to be corrupt,
they’re paying attention not only to the economic incentives
or the chance of being caught,
but what they think other people are doing,
whether they think other people are doing it, and also to their self concept,
how the action will appear to themselves.
And then, finally, for me, the research challenges
to connect these questions with all the other themes in this issue
to understand how a group of nuns wired together in a connectome
can construct something as abstract as the idea of another mind.
On the other hand, what happens when you get many brains like this
linked together all thinking about each other,
what new levels of complexity emerge?
And that’s the theme of the next two talks.
Thank you.