0:00:00.760,0:00:02.856
There's a man out there, somewhere,

0:00:02.880,0:00:05.856
who looks a little bit[br]like the actor Idris Elba,

0:00:05.880,0:00:08.256
or at least he did 20 years ago.

0:00:08.280,0:00:10.096
I don't know anything else about him,

0:00:10.120,0:00:12.016
except that he once saved my life

0:00:12.040,0:00:13.680
by putting his own life in danger.

0:00:14.600,0:00:19.976
This man ran across four lanes of freeway[br]traffic in the middle of the night

0:00:20.000,0:00:21.776
to bring me back to safety

0:00:21.800,0:00:24.576
after a car accident[br]that could have killed me.

0:00:24.600,0:00:27.256
And the whole thing[br]left me really shaken up, obviously,

0:00:27.280,0:00:31.256
but it also left me with this[br]kind of burning, gnawing need

0:00:31.280,0:00:32.920
to understand why he did it,

0:00:33.760,0:00:36.536
what forces within him[br]caused him to make the choice

0:00:36.560,0:00:38.416
that I owe my life to,

0:00:38.440,0:00:42.056
to risk his own life[br]to save the life of a stranger?

0:00:42.080,0:00:47.120
In other words, what are the causes of his[br]or anybody else's capacity for altruism?

0:00:47.840,0:00:49.856
But first let me tell you what happened.

0:00:49.880,0:00:51.336
That night, I was 19 years old

0:00:51.360,0:00:53.736
and driving back to my home[br]in Tacoma, Washington,

0:00:53.760,0:00:55.576
down the Interstate 5 freeway,

0:00:55.600,0:00:58.136
when a little dog[br]darted out in front of my car.

0:00:58.160,0:01:00.496
And I did exactly[br]what you're not supposed to do,

0:01:00.520,0:01:01.880
which is swerve to avoid it.

0:01:02.480,0:01:04.920
And I discovered why[br]you're not supposed to do that.

0:01:05.319,0:01:07.056
I hit the dog anyways,

0:01:07.080,0:01:09.696
and that sent the car into a fishtail,

0:01:09.720,0:01:12.296
and then a spin across the freeway,

0:01:12.320,0:01:15.896
until finally it wound up[br]in the fast lane of the freeway

0:01:15.920,0:01:18.856
faced backwards into oncoming traffic

0:01:18.880,0:01:20.240
and then the engine died.

0:01:21.480,0:01:25.040
And I was sure in that moment[br]that I was about to die too,

0:01:25.880,0:01:27.096
but I didn't

0:01:27.120,0:01:29.856
because of the actions[br]of that one brave man

0:01:29.880,0:01:31.376
who must have made the decision

0:01:31.400,0:01:34.416
within a fraction of a second[br]of seeing my stranded car

0:01:34.440,0:01:38.696
to pull over and run[br]across four lanes of freeway traffic

0:01:38.720,0:01:40.656
in the dark

0:01:40.680,0:01:42.656
to save my life.

0:01:42.680,0:01:45.576
And then after he got my car working again

0:01:45.600,0:01:49.216
and got me back to safety[br]and made sure I was going to be all right,

0:01:49.240,0:01:50.776
he drove off again.

0:01:50.800,0:01:53.136
He never even told me his name,

0:01:53.160,0:01:55.320
and I'm pretty sure[br]I forgot to say thank you.

0:01:56.440,0:01:58.376
So before I go any further,

0:01:58.400,0:01:59.856
I really want to take a moment

0:01:59.880,0:02:02.680
to stop and say thank you[br]to that stranger.

0:02:03.280,0:02:05.000
(Applause)

0:02:10.919,0:02:12.136
I tell you all of this

0:02:12.160,0:02:16.376
because the events of that night changed[br]the course of my life to some degree.

0:02:16.400,0:02:18.016
I became a psychology researcher,

0:02:18.040,0:02:22.816
and I've devoted my work to understanding[br]the human capacity to care for others.

0:02:22.840,0:02:25.176
Where does it come from,[br]and how does it develop,

0:02:25.200,0:02:27.440
and what are the extreme forms[br]that it can take?

0:02:28.120,0:02:31.296
These questions are really important[br]to understanding basic aspects

0:02:31.320,0:02:32.560
of human social nature.

0:02:33.320,0:02:35.416
A lot of people,[br]and this includes everybody

0:02:35.440,0:02:38.336
from philosophers[br]and economists to ordinary people

0:02:38.360,0:02:41.616
believe that human nature[br]is fundamentally selfish,

0:02:41.640,0:02:45.816
that we're only ever really motivated[br]by our own welfare.

0:02:45.840,0:02:50.136
But if that's true, why do some people,[br]like the stranger who rescued me,

0:02:50.160,0:02:52.656
do selfless things,[br]like helping other people

0:02:52.680,0:02:55.120
at enormous risk and cost to themselves?

0:02:55.880,0:02:57.176
Answering this question

0:02:57.200,0:03:01.296
requires exploring the roots[br]of extraordinary acts of altruism,

0:03:01.320,0:03:03.696
and what might make people[br]who engage in such acts

0:03:03.720,0:03:05.576
different than other people.

0:03:05.600,0:03:08.680
But until recently, very little work[br]on this topic had been done.

0:03:09.920,0:03:11.736
The actions of the man who rescued me

0:03:11.760,0:03:14.736
meet the most stringent[br]definition of altruism,

0:03:14.760,0:03:17.376
which is a voluntary, costly behavior

0:03:17.400,0:03:19.840
motivated by the desire[br]to help another individual.

0:03:20.640,0:03:23.760
So it's a selfless act[br]intended to benefit only the other.

0:03:24.560,0:03:27.120
What could possibly[br]explain an action like that?

0:03:28.120,0:03:30.056
One answer is compassion, obviously,

0:03:30.080,0:03:31.880
which is a key driver of altruism.

0:03:32.520,0:03:34.136
But then the question becomes,

0:03:34.160,0:03:36.920
why do some people[br]seem to have more of it than others?

0:03:38.120,0:03:42.016
And the answer may be that the brains[br]of highly altruistic people

0:03:42.040,0:03:44.240
are different in fundamental ways.

0:03:45.120,0:03:47.016
But to figure out how,

0:03:47.040,0:03:49.160
I actually started from the opposite end,

0:03:50.160,0:03:51.360
with psychopaths.

0:03:52.680,0:03:55.776
A common approach to understanding[br]basic aspects of human nature,

0:03:55.800,0:03:57.816
like the desire to help other people,

0:03:57.840,0:04:00.976
is to study people[br]in whom that desire is missing,

0:04:01.000,0:04:03.120
and psychopaths are exactly such a group.

0:04:04.200,0:04:06.576
Psychopathy is a developmental disorder

0:04:06.600,0:04:08.696
with strongly genetic origins,

0:04:08.720,0:04:11.616
and it results in a personality[br]that's cold and uncaring

0:04:11.640,0:04:15.164
and a tendency to engage in antisocial[br]and sometimes very violent behavior.

0:04:16.040,0:04:19.296
Once my colleagues and I[br]at the National Institute of Mental Health

0:04:19.320,0:04:21.935
conducted some of the first ever[br]brain imaging research

0:04:21.959,0:04:24.096
of psychopathic adolescents,

0:04:24.120,0:04:26.976
and our findings, and the findings[br]of other researchers now,

0:04:27.000,0:04:29.296
have shown that people[br]who are psychopathic

0:04:29.320,0:04:32.240
pretty reliably exhibit[br]three characteristics.

0:04:33.160,0:04:37.776
First, although they're not generally[br]insensitive to other people's emotions,

0:04:37.800,0:04:41.576
they are insensitive to signs[br]that other people are in distress.

0:04:41.600,0:04:42.816
And in particular,

0:04:42.840,0:04:46.736
they have difficulty recognizing[br]fearful facial expressions like this one.

0:04:46.760,0:04:50.456
And fearful expressions convey[br]urgent need and emotional distress,

0:04:50.480,0:04:53.096
and they usually elicit[br]compassion and a desire to help

0:04:53.120,0:04:54.376
in people who see them,

0:04:54.400,0:04:57.096
so it makes sense that people[br]who tend to lack compassion

0:04:57.120,0:04:59.240
also tend to be insensitive to these cues.

0:05:00.520,0:05:01.736
The part of the brain

0:05:01.760,0:05:04.656
that's the most important[br]for recognizing fearful expressions

0:05:04.680,0:05:05.936
is called the amygdala.

0:05:05.960,0:05:09.376
There are very rare cases of people[br]who lack amygdalas completely,

0:05:09.400,0:05:13.256
and they're profoundly impaired[br]in recognizing fearful expressions.

0:05:13.280,0:05:15.656
And whereas healthy adults and children

0:05:15.680,0:05:18.296
usually show big spikes[br]in amygdala activity

0:05:18.320,0:05:20.456
when they look at fearful expressions,

0:05:20.480,0:05:23.616
psychopaths' amygdalas[br]are underreactive to these expressions.

0:05:23.640,0:05:25.296
Sometimes they don't react at all,

0:05:25.320,0:05:27.940
which may be why they have[br]trouble detecting these cues.

0:05:29.240,0:05:32.376
Finally, psychopaths' amygdalas[br]are smaller than average

0:05:32.400,0:05:34.000
by about 18 or 20 percent.

0:05:34.920,0:05:38.736
So all of these findings[br]are reliable and robust,

0:05:38.760,0:05:40.216
and they're very interesting.

0:05:40.240,0:05:41.896
But remember that my main interest

0:05:41.920,0:05:45.456
is not understanding[br]why people don't care about others.

0:05:45.480,0:05:47.040
It's understanding why they do.

0:05:47.880,0:05:50.176
So the real question is,

0:05:50.200,0:05:52.456
could extraordinary altruism,

0:05:52.480,0:05:54.696
which is the opposite of psychopathy

0:05:54.720,0:05:58.136
in terms of compassion[br]and the desire to help other people,

0:05:58.160,0:06:02.176
emerge from a brain that is also[br]the opposite of psychopathy?

0:06:02.200,0:06:04.440
A sort of antipsychopathic brain,

0:06:05.880,0:06:08.976
better able to recognize[br]other people's fear,

0:06:09.000,0:06:11.416
an amygdala that's more reactive[br]to this expression

0:06:11.440,0:06:13.280
and maybe larger than average as well?

0:06:13.920,0:06:15.936
As my research has now shown,

0:06:15.960,0:06:17.416
all three things are true.

0:06:17.440,0:06:18.696
And we discovered this

0:06:18.720,0:06:21.736
by testing a population[br]of truly extraordinary altruists.

0:06:21.760,0:06:24.416
These are people who have given[br]one of their own kidneys

0:06:24.440,0:06:25.640
to a complete stranger.

0:06:26.600,0:06:29.696
So these are people who have volunteered[br]to undergo major surgery

0:06:29.720,0:06:32.336
so that one of their own[br]healthy kidneys can be removed

0:06:32.360,0:06:34.416
and transplanted into a very ill stranger

0:06:34.440,0:06:36.480
that they've never met and may never meet.

0:06:37.040,0:06:39.840
"Why would anybody do this?"[br]is a very common question.

0:06:40.520,0:06:41.896
And the answer may be

0:06:41.920,0:06:44.176
that the brains of these[br]extraordinary altruists

0:06:44.200,0:06:46.000
have certain special characteristics.

0:06:47.040,0:06:50.256
They are better at recognizing[br]other people's fear.

0:06:50.280,0:06:53.696
They're literally better at detecting[br]when somebody else is in distress.

0:06:53.720,0:06:58.376
This may be in part because their amygdala[br]is more reactive to these expressions.

0:06:58.400,0:07:01.336
And remember, this is the same part[br]of the brain that we found

0:07:01.360,0:07:03.696
was underreactive[br]in people who are psychopathic.

0:07:03.720,0:07:06.616
And finally, their amygdalas[br]are larger than average as well,

0:07:06.640,0:07:07.856
by about eight percent.

0:07:07.880,0:07:09.616
So together, what these data suggest

0:07:09.640,0:07:13.256
is the existence of something[br]like a caring continuum in the world

0:07:13.280,0:07:16.816
that's anchored at the one end[br]by people who are highly psychopathic,

0:07:16.840,0:07:19.336
and at the other by people[br]who are very compassionate

0:07:19.360,0:07:21.280
and driven to acts of extreme altruism.

0:07:22.760,0:07:26.696
But I should add that what makes[br]extraordinary altruists so different

0:07:26.720,0:07:29.416
is not just that they're[br]more compassionate than average.

0:07:29.440,0:07:30.656
They are,

0:07:30.680,0:07:32.576
but what's even more unusual about them

0:07:32.600,0:07:34.696
is that they're compassionate[br]and altruistic

0:07:34.720,0:07:37.656
not just towards people[br]who are in their own innermost circle

0:07:37.680,0:07:39.656
of friends and family. Right?

0:07:39.680,0:07:42.936
Because to have compassion for people[br]that you love and identify with

0:07:42.960,0:07:45.160
is not extraordinary.

0:07:46.040,0:07:50.216
Truly extraordinary altruists' compassion[br]extends way beyond that circle,

0:07:50.240,0:07:52.456
even beyond their wider[br]circle of acquaintances

0:07:52.480,0:07:55.416
to people who are outside[br]their social circle altogether,

0:07:55.440,0:07:56.976
total strangers,

0:07:57.000,0:07:58.600
just like the man who rescued me.

0:07:59.960,0:08:03.456
And I've had the opportunity now[br]to ask a lot of altruistic kidney donors

0:08:03.480,0:08:07.856
how it is that they manage to generate[br]such a wide circle of compassion

0:08:07.880,0:08:11.216
that they were willing to give[br]a complete stranger their kidney.

0:08:11.240,0:08:14.736
And I found it's a really difficult[br]question for them to answer.

0:08:14.760,0:08:18.816
I say, "How is it that[br]you're willing to do this thing

0:08:18.840,0:08:20.816
when so many other people don't?

0:08:20.840,0:08:23.256
You're one of fewer than 2,000 Americans

0:08:23.280,0:08:25.896
who has ever given a kidney to a stranger.

0:08:25.920,0:08:27.760
What is it that makes you so special?"

0:08:28.400,0:08:29.680
And what do they say?

0:08:31.400,0:08:33.320
They say, "Nothing.

0:08:34.200,0:08:35.976
There's nothing special about me.

0:08:36.000,0:08:37.799
I'm just the same as everybody else."

0:08:39.200,0:08:42.296
And I think that's actually[br]a really telling answer,

0:08:42.320,0:08:46.160
because it suggests that the circles[br]of these altruists don't look like this,

0:08:47.240,0:08:49.216
they look more like this.

0:08:49.240,0:08:50.480
They have no center.

0:08:51.320,0:08:53.736
These altruists literally[br]don't think of themselves

0:08:53.760,0:08:56.016
as being at the center of anything,

0:08:56.040,0:08:59.000
as being better or more inherently[br]important than anybody else.

0:09:00.000,0:09:03.216
When I asked one altruist[br]why donating her kidney made sense to her,

0:09:03.240,0:09:05.960
she said, "Because it's not about me."

0:09:07.040,0:09:08.776
Another said,

0:09:08.800,0:09:11.056
"I'm not different. I'm not unique.

0:09:11.080,0:09:14.416
Your study here is going to find out[br]that I'm just the same as you."

0:09:14.440,0:09:18.536
I think the best description[br]for this amazing lack of self-centeredness

0:09:18.560,0:09:20.416
is humility,

0:09:20.440,0:09:23.536
which is that quality[br]that in the words of St. Augustine

0:09:23.560,0:09:25.080
makes men as angels.

0:09:26.120,0:09:27.816
And why is that?

0:09:27.840,0:09:30.616
It's because if there's[br]no center of your circle,

0:09:30.640,0:09:33.176
there can be no inner rings[br]or outer rings,

0:09:33.200,0:09:36.096
nobody who is more or less worthy[br]of your care and compassion

0:09:36.120,0:09:37.320
than anybody else.

0:09:37.920,0:09:41.416
And I think that this is what really[br]distinguishes extraordinary altruists

0:09:41.440,0:09:42.680
from the average person.

0:09:43.400,0:09:46.976
But I also think that this is a view[br]of the world that's attainable by many

0:09:47.000,0:09:48.976
and maybe even most people.

0:09:49.000,0:09:51.256
And I think this[br]because at the societal level,

0:09:51.280,0:09:55.000
expansions of altruism and compassion[br]are already happening everywhere.

0:09:55.920,0:09:58.376
The psychologist Steven Pinker[br]and others have shown

0:09:58.400,0:10:01.656
that all around the world people[br]are becoming less and less accepting

0:10:01.680,0:10:04.136
of suffering in ever-widening[br]circles of others,

0:10:04.160,0:10:07.216
which has led to declines[br]of all kinds of cruelty and violence,

0:10:07.240,0:10:10.760
from animal abuse to domestic violence[br]to capital punishment.

0:10:11.480,0:10:14.296
And it's led to increases[br]in all kinds of altruism.

0:10:14.320,0:10:17.416
A hundred years ago, people[br]would have thought it was ludicrous

0:10:17.440,0:10:18.936
how normal and ordinary it is

0:10:18.960,0:10:22.256
for people to donate[br]their blood and bone marrow

0:10:22.280,0:10:23.920
to complete strangers today.

0:10:24.720,0:10:26.816
Is it possible that[br]a hundred years from now

0:10:26.840,0:10:29.416
people will think[br]that donating a kidney to a stranger

0:10:29.440,0:10:30.896
is just as normal and ordinary

0:10:30.920,0:10:33.936
as we think donating blood[br]and bone marrow is today?

0:10:33.960,0:10:35.160
Maybe.

0:10:35.800,0:10:38.696
So what's at the root[br]of all these amazing changes?

0:10:38.720,0:10:40.496
In part it seems to be

0:10:40.520,0:10:43.720
increases in wealth[br]and standards of living.

0:10:44.600,0:10:47.336
As societies become[br]wealthier and better off,

0:10:47.360,0:10:49.976
people seem to turn[br]their focus of attention outward,

0:10:50.000,0:10:53.856
and as a result, all kinds of altruism[br]towards strangers increases,

0:10:53.880,0:10:58.600
from volunteering to charitable donations[br]and even altruistic kidney donations.

0:10:59.440,0:11:02.416
But all of these changes also yield

0:11:02.440,0:11:05.656
a strange and paradoxical result,

0:11:05.680,0:11:09.216
which is that even as the world is[br]becoming a better and more humane place,

0:11:09.240,0:11:10.456
which it is,

0:11:10.480,0:11:13.176
there's a very common perception[br]that it's becoming worse

0:11:13.200,0:11:15.240
and more cruel, which it's not.

0:11:16.080,0:11:17.896
And I don't know exactly why this is,

0:11:17.920,0:11:21.496
but I think it may be[br]that we now just know so much more

0:11:21.520,0:11:24.696
about the suffering[br]of strangers in distant places,

0:11:24.720,0:11:27.136
and so we now care a lot more

0:11:27.160,0:11:29.360
about the suffering[br]of those distant strangers.

0:11:30.240,0:11:33.936
But what's clear is the kinds[br]of changes we're seeing show

0:11:33.960,0:11:36.416
that the roots of altruism and compassion

0:11:36.440,0:11:39.456
are just as much a part of human nature[br]as cruelty and violence,

0:11:39.480,0:11:41.176
maybe even more so,

0:11:41.200,0:11:45.256
and while some people do seem[br]to be inherently more sensitive

0:11:45.280,0:11:47.376
to the suffering of distant others,

0:11:47.400,0:11:50.176
I really believe that the ability[br]to remove oneself

0:11:50.200,0:11:51.976
from the center of the circle

0:11:52.000,0:11:56.056
and expand the circle of compassion[br]outward to include even strangers

0:11:56.080,0:11:58.880
is within reach for almost everyone.

0:12:00.080,0:12:01.296
Thank you.

0:12:01.320,0:12:08.898
(Applause)