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Paul Bloom is the Brooks and Suzanne Ragen Professor of Psychology at Yale University. An internationally recognized expert on the psychology of child development, social reasoning, and morality, he has won[…]

Give Paul Bloom one hour, and he’ll teach you “the psychology of everything.” Through the case studies of compassion, racism, and sex, Dr. Bloom explores the intrinsic fundamentals of human nature, including some of our most intriguing tendencies, such as the kindness of babies, stereotyping (which can be both detrimental and beneficial), and our universal sense of beauty. Additional topics addressed in the lecture include: “What do studies suggest is the number one characteristic that males and females look for in a mate?”, “How can I get someone to have compassion for causes I care about?”, “Are we all unconscious racists?”, and even, “What do the porn preferences of monkeys tells us about our own sexual choices?”

Hello, my name is Paul Bloom and I’m a Professor of Psychology at Yale University.  And what I want to do today is present a brief introduction to psychology, which is the science of the human mind.  

Now, I’m admittedly biased, but I think psychology is the most interesting of all scientific fields.  It’s the most interesting because it’s about us.  It’s about the most important and intimate aspects of our lives.  So psychologists study everything from language, perception, memory, motivation, dreams, love, hate.  We study the development of a child.  We study mental illnesses like schizophrenia and psychopathy, we study morality, we study happiness. 

Now, psychology is such a huge field that it breaks up into different subfields.  Some psychologists study neuroscience, which is the study how the brain gives rise to mental life.  Others, like me, are Developmental Psychologists.  We study what happens to make a baby turn into a child and a child turn into adults.  We study what makes a baby turn into a child and a child turn into an adult.  We ask questions like, how does a baby think about the world?  What do we start off knowing?  What do we have to learn?  

Other psychologists are Social Psychologists. They study human interaction.  What’s the nature of prejudice?  How do we persuade one another? 

Some Psychologists are Cognitive Psychologists.  What that means is they study the mind as a computational device looking particularly at capacities like language, perception, memory, and decision-making.  Some Psychologists are Evolutionary Psychologists, which means they’re particularly interested in biological origin of the human mind.  

There are Evolutionary Psychologists.  Evolutionary Psychologists are particularly interested in the evolutionary origin of our psychologies.  So they study the mind with an eye towards how it has evolved.  What adaptive problems it’s been constructed to solve.  

Finally, there’s clinical psychology.  For many people, this is what psychology means.  Many people associate psychology with clinical psychology, and in fact, it’s a very important aspect of psychology.  Clinical psychologists are interested in the diagnosis that the causes and the treatment of mental disorders, disorders like schizophrenia, depression and anxiety disorders.  It would be impossible for me to provide a full spectrum introduction to all of these sub fields of psychology in the time I have.  

So what I’m going to do instead is I’m going to focus on three case studies. I’m gong to focus on compassion, racism, and sex.  I’ve chosen these case studies for two reasons.  First, each of them is particularly interesting in its own light.  These are questions we’re interested in as people, as scientists, but also in our every day lives.  And I want to try to persuade you that psychologists have some interesting things to say about them.  

Second, together they illustrate the range of approaches that psychologists use.  The sort of theories that we construct, the sorts of methods we use when approaching a domain.  I want to try to give you a feeling for what psychology looks like when we actually carry it out.  

The first case study is compassion.  Compassion… by what I mean by compassion is concern for other people.  This is particularly interesting to me.  This is my own research program and my own laboratory at Yale; we look at the emergence of morality in babies and young children.  And we particularly focus on the emergence of compassion.  At what point in development do babies care about others?  At what point in development does feelings of empathy and sympathy, sometimes anger, guilt, other moral emotions.  How do they arise?  To what extent are they built in?  To what extent do they have to be learned?  

As a starting point, I have here a picture of a baby and inside the baby’s head is the baby’s brain.  The baby’s brain is an extraordinary computing machine.  

The baby’s brain is composed of neurons.  Now neurons are basic cells that process and transmit information.  They receive input from other neurons and then if the sum of the input is sufficiently high, they fire.  The brain does its work through collections of neurons, through what you would call neuro networks on neuro circuits.  

Now looked at in that way, the baby’s brain is extraordinarily impressive.  It contains roughly 100 billion neurons.  Since all of the thinking is done through connections between the neurons, what happens as the baby grows if more and more connections are made.  And by one estimate, there’s about 1.8 million connections between neurons that are created per second.  To give you a feeling of the complexity of the baby’s brain, I use an analogy from Jeff Hawkins.  Imagine a football stadium.   Fill it up with cooked spaghetti, then shrink it to the size of a soccer ball.  Then make it much, much, much denser.  And then you’ll have some understanding of how much is going on inside a brain, inside even a baby’s brain.  

Now, that much we know for sure, but where the real debate goes on concerns the nature of that computational structure.  The nature of what’s going on with all of those neuro networks and neuro circuits.  There’s one of view that is held by many philosophers and many psychologists that the brain starts off as a blank slate, what the philosopher, John Locke, called “a Tabula Rasa.”  And what goes on in development, the point of all those connections per second is learning, is sucking up information from the environment.  The baby starts off knowing nothing and turns into an adult, by virtue of absorbing information at a tremendously powerful rate.  That’s one view.  

Many philosophers and many psychologists, including me and my colleagues are more enamored of another view.  We don’t deny that learning takes place, but we would argue that in addition to that, there is an extraordinary early understanding, early specialization.  The brain could better be understood in terms of what the psychologists, Leda Cosmides and John Tooby, described as a Swiss Army knife, has many different parts.  And each part is specialized for a different function.  

Now, so much of the action in psychology has been a running debate over which view is right.  So for instance, in the domain of language, many people have argued that there’s nothing special with the language.  We come to know, we come to use language because we’re just very powerful learners.  Other people, most notably the linguists, Noam Chomsky, and people have followed from his work; have argued that there is a specialized mechanism for language; language organ or language module or language instinct.  Learning needs to be done, but it’s done through this specialized system.  

Now, I’m not going to talk about language today, but there’s another debate, which I am going to talk about.  And this concerns morality, both moral judgments of right and wrong, but also moral feelings including compassion.  Many people would argue that in that regard, the baby starts off with nothing.  

Many people would agree with the classic Onion headline, a satirical newspaper, which says:  “New study reveals most children unrepentant sociopaths.”  The idea is that children start off immoral, monsters or if not monsters, at least they know not from good and evil.  This is not the view which I think is supported by the data.  I think there is now more and more data in support of a different view of compassion.  One that was nicely summarized by Thomas Jefferson.  

So Thomas Jefferson wrote:  “The moral sense or conscious is as much a part of man as his leg or arm.  It is given to all human beings in stronger or weaker degree as **** of members has given them in a greater or lesser degree.”  This claim, the idea that we grow morality, morality is part of our nature, was supported by Thomas Jefferson’s contemporary, Adam Smith, in Europe at the same time.  Sorry… was supported by Thomas Jefferson’s contemporary, Adam Smith.  And Adam gives an example of this.  He points out that it is a part of our nature to feel pain at the pain of others.  As he writes:  “When we see a stroke aimed and just ready to fall upon the leg or arm of another person, we naturally shrink and draw back our own leg or arm.  And when it does fall, we feel it in some measure and are hurt by it as well as the sufferer.”  And here is an illustration of this act of empathy taking place.  

Now we know this is true for children.  In fact, we know this is true for babies.  One way to make a baby cry is to expose it to cries of other babies.  There’s sort of contagiousness to the crying.  It’s not just crying.  We also know that if a baby sees another human in silent pain, it will distress the baby.  It seems part of our very nature is to suffer at the suffering of others.  

We know that young babies, as they become capable of moving voluntarily will share.  They will share food, for instance, with their siblings and with kids that are around.  They will sooth.  If they see somebody else in pain, even the youngest of toddlers will try to reach out and pat the person.  Maybe hand over a toy.  

There’s some lovely studies finding that slightly older children are able to help others when they see somebody who is unable to fulfill a goal, they’ll seek out to come to their aid.    

So one elegant demonstration of this comes from a recent set of experiments by the psychologist, Felix Warneken and Michael Tomasello, where they take a toddler, put him or her in a situation where an adult is in some sort of mild distress and see if the toddler will voluntarily help, even without any prompting.  And they find that toddlers typically do.  There seems to be some sort of impulse in us that’s altruistic, that’s kind, that’s compassionate.  

Now, in all of these cases; however, the kindness that we see seems to apply to people who are close to us, who are either physically in our proximity or who are our siblings or our parents or our friends.  

So the question arises, how broad does this compassion extend?  Now some people would argue that we start off with a very broad compassion, we would extend it to all individuals, to all people.  But there’s evidence support a somewhat different view, which is, there’s a moral instinct in us, there’s a moral sense in us, but it’s initially very narrow.  It’s only created by those close to us.  And our feelings towards others are in fact, not positive at all, they aren’t compassionate at all.  In fact, our natural default feelings towards a stranger, far from being compassionate, is actually some sort of mixture of fear and hatred.  

We see this in all sorts of different ways.  So in young children, we see it in what’s called, “stranger anxiety.”  At around nine months of age, babies start becoming panicked at the presence of strangers.  They fear strangers.  And developmental psychologists have helpfully called it “stranger anxiety” and it seems to capture a universal part of development where the other is thought of as dangerous.  

This sort of stranger anxiety fades in some cultures.  If you were to find yourself in an airport in a new city, you’re not likely to have a panic attack because you’re surrounded by people you don’t know, but in small scale human societies, it might never go away.  In a situation when an individual is raised with a few hundred other individuals around them, that is their circle of compassion.  And their response to others is not positive.  This is an observation that’s been made by many anthropologists who study small scale societies.  So for instance, anthropologist, Jared Diamond, talking about small scale societies in **** New Guinea writes, “To venture out of one’s territory to meet other humans, even if they lived only a few miles away, was equivalent to suicide.  Many years before, Margaret Meade was talking about the lifestyles of what were called at the time, “primitive cultures.”  And she is famously a supporter of these lifestyles.  She argues that the Western world would be much better if we were to adopt the customs and thoughts and ideas, particularly in regard to sexuality of these other societies.  But she was very honest and very blunt about how members of these societies treat strangers. 
She writes:  “Most primitive tribes feel that if you run across one of those sub humans from a rival group in the forest, the most appropriate thing to do is bludgeon them to death.”  

I’ve talked about fear and hatred, but there’s a third sort of response that we often give to strangers.  This is disgust.  Disgust is what Paul Rozin described as the “body/soul emotion,” is a human universal.  Humans everywhere are disgusted by certain things.  We are disgusted by feces, urine, blood, vomit, rotten flesh, and most meat.  Disgust has a characteristic facial response and its easy part of our natures.  Now, if it was limited to food and cockroaches and that sort of thing, it wouldn’t have anything to do with my talk on compassion.  But what’s most interesting is that we’re often disgusted by other people.  But what’s most interesting is that we are often disgusted by other people.  Particularly, we’re often disgusted by strange people.   

And this is an observation that Charles Darwin, who is a wonderful observer of human nature, made.  Darwin wrote:  “In Tierra del Fuego, a native touched with his fingers some cold preserved meat and plainly showed disgust at the softness.  Whilst I felt utter disgust of my food being touched by a naked savage, thought his hands did not appear dirty.”  

We have laboratory research that explores the relationship between feelings of disgust and feelings towards out groups.  So we know for instance that people differ in how easily disgusted they are.  You do a survey of people.  You ask them questions like, how badly would this bother you.  So one of the questions might be, you have to pick up a dead cat with your hands.  And there’s some people who say, “uh, whatever.”  Some people, “Oh my god!  I’d rather die” or, you sit on a city bus seat and it’s warm from the last person who was on it.  And some people crack up, well why would that bother me?  Other people say, “That’s very disturbing.”  

People differ in how sensitive they are to disgust.  It turns out that where you stand with regard to disgust correlates with your feelings about out groups.  It correlates with your feelings about immigrants; it correlates with your feelings about sexual minorities, in particular male homosexuals.  The more easily disgusted you are, the more aversion you find to these others.  

We also know this experimentally.   We know that by making people be disgusted, we can make them meaner.  I’ll give you an example of this.  This is from a study I was involved with, with David Pizarro at Cornell University as the lead investigator.  What we did was we brought people into the lab… into a lab at Cornell.  And we asked him all sorts of questions regarding their feelings towards different groups and different policies.  What do you think of African-Americans?  What do you think of gay men?  What do you think of welfare?  What do you think of immigration?  And so on and so forth.  Half the people just filled it out and went home. 

The other half of the subjects went into the room, got the same survey.  But the difference was, before they entered the room, we sprayed the room with a fart spray.  That’s the first experiment I’ve ever been involved with that used a fart spray.  People would be kind of grossed out.  And it would make them meaner.  Not towards everything, but it would make them particularly meaner towards out groups, like male homosexuals.  And this supports the idea that there’s a connection in our minds between a visceral emotion of disgust and our feelings towards others.  

So what I’ve argued is, we do have a natural compassion, but it’s limited.  It does not naturally extend to strangers.  It does not naturally extend to others.  For them our reaction might be hatred, fear, and disgust.  But that raises a puzzle because you and me and everyone else we know can extend our compassion to strangers, to put it in the language that the philosopher Peter Singer has used, “Our moral circle has expanded.”  It might be that our ancestors, it might be the people in small scale societies only cared about their family and friends, but we have a broader circle of compassion.  We think about we care about people in other countries.  We care about people from other races.  We care about people we’ve never seen before and we never will see. 

When some sort of disaster strikes like a tsunami or a hurricane or earthquake, many of us give our resources, even our blood, to help out people we’ve never met before.  And that poses a neat psychological puzzle.  

What forces take our narrow moral circle, our narrow scope of compassion and make it bigger and expand it to care for these others?  Now I think that there are a lot of different answers to that question.  Robert Wright, for instance, has argued that one force in expanding the moral circle has been human interconnections in commerce, in international travel and so on.  The more people you know, the more people you have contact with, the more we are interconnected in the world, the more you might care about them in a sort of self-interested altruism where you care about them because they’re fates are intertwined with yours.  And I think that there’s a lot of value in that insight.  

But I want to focus on a different, maybe more psychological mechanism.  A mechanism that happens to individuals as they get older, a part of development, which is, their sympathies expand because of a certain sort of persuasion.  I want to suggest that there is psychological evidence that supports the idea that we can expand our compassion, our moral circle to far away strangers by being made to think of them as if they are individual people.  In particular, we think of them as if they’re our friends and family.  We think of them as if they are right in front of us. 
Now, the importance of thinking about concrete individuals when it comes to kindness is not an idea psychologists were forced to come out with, it’s very well-known, thought of by monsters and by saints. 

Joseph Stalin famously said, “A single death is a tragedy, a million deaths is a statistic.” 

And Mother Theresa presented a similar sentiment when she said, “If I look at the mass, I will never act.  If I look at the one, I will.”  

Psychologists like Paul Slovic has explored this in the lab.  So for instance, they would do a study where they would have an appeal for a charity.  And in fact, they would take the money they got and send it to the charity.  And they would, for one group of subjects, describe the problem in terms of statistics, in terms of numbers, in terms of the millions of people suffering, a sort of suffering a proportion of the population who is in desperate need. And they found that people would give say, roughly a dollar. 

For the other group, they didn’t bother with statistics at all.  They didn’t bother trying to impress them with the huge number of people suffering.  Rather, they told them a story.  They told them a story about a single individual.  They had a picture of that individual, they gave her a name.  And when you do that, you find that people are far more generous.  It’s a far more powerful effect on their compassion.  They will give, roughly, twice as much.  

Now, this is not a secret.  It is not something only psychologists know.  Charities, when they try to appeal for people’s help, won’t throw numbers at you.  They typically won’t because they know that doesn’t work.  The way to extend people’s compassion, the way to motivate altruistic action is to appeal to some very natural, very hardwired systems within us that respond to individual people.  And so charities will draw your attention, will appeal to you by focusing on the individual.  

I know this from a personal story.  When I was a graduate student, I was having an argument with a philosopher friend of mine.  And I was telling him, I was very persuaded by some stuff I read that rich Westerners don’t give anywhere near enough money to the starving millions around the world.  And I was giving him such a hard time about that.  And at some point, totally sick of me, he says, “How much do you give to charity?”  And I’m thinking, well, I’m making a theoretical point here.  **** I don’t give anything to charity.  So I figured, I felt so bad about this, I contacted one of the… a major charity, actually Plan U.S.A. and asked them for information about how to give to them.  And they sent me a packet.  And I remember opening up the packet and I remember expecting to see graphs and numbers and all sorts of information.  And they were so much smarter than that ‘cause I opened up the package and what they had sent me was a child.  They had a photograph of the child, they had a letter he wrote, and they said to me, “Look, we know that you’re not promising to give to us, you just want information, but if you were to give, it would go to that individual.  That would be the life you would save.”  It worked for me; I think it’s a tremendously persuasive way for a charity to work.  And I think more generally, as part of the story for how our compassion can get bigger and bigger.  

This really matters.  People talk about moral progress.  People like Peter Singer, Robert Wright, Steven Pinker, have argued that through our history, the circle of… our moral circles have been expanding.  It’s not just through individuals as they get older; rather societies have broader and broader moral circles.  We now live in a world where people believe we have moral obligations to other races, other nationalities that sexism and racism are immoral.  Some of us believe we have obligations toward non-human animals.  And this has been happening because of stories, because of persuasion and because people come to moral insights and use the power of stories to convey them.

Martha Nussbaum gives a historical example with regard to Greek tragedies. She writes… I have to go **** this.  “Although all of the future citizens who saw ancient tragedies were male, they were asked to have empathy with the suffering of many whose lot could never be theirs, such as Trojans and Persians and Africans, such as wives and daughters and mothers.”  

And if you were to doubt the importance of this, consider the end of slavery in the United States.  There are a lot of different factors that led to the end of slavery, but many historians would argue that one of the forces that led many white Americans to believe slavery was wrong was persuasion, in particular, it was the work of the author Harriett Beecher Stowe in her book, Uncle Tom’s Cabin.  

In particular, it was the work of Harriet Beecher Stowe in her book, Uncle Tom’s Cabin.  In this book, she didn’t make logical arguments; she didn’t make theological points or philosophical proposals.  

Rather, she got her readers to extend their sympathies.  And this had a profound effect.  It had a profound effect persuading them that slavery was wrong and changing the fate of the world.  

The second case study I want to talk about is racism.  And I want to begin by making a connection to a branch of cognitive psychology.  In particular the brand of cognitive psychology that deals with how we make sense of the world.  How we naturally form categories of the things we see and the things we interact with.  

Cognitive psychologists have pointed out that we… that in order to survive in the world, we have to make generalizations.  You probably have never seen those three pictures I have up here, but you immediately know that one is a dog and one is an apple and one is a chair.  You will also have intuitions about these things… you’ll make generalizations.  You’ll believe the dog can bark, the apple is something you can eat, a chair is something you can sit on.  Now, you probably also realize that there are exceptions to this.  Some dogs are silent, some apples are poisonous, some chairs will collapse if you sit on them, but still if you couldn’t make those generalizations, if you didn’t recognize that some properties tend to co-occur with some objects, you would be helpless in the world.  You wouldn’t know what to eat, you wouldn’t know how anything would react; you wouldn’t survive.  

Part of being a successful human, in fact, part of being any successful animal is being able to learn.  And a good part of what learning is is to make statistical generalizations on the basis of limited experience.  You eat a thousand apples, they all taste pretty good, you conclude, I can eat apples, apples taste good.  And when you’re hungry, you reach for the apple.  This is adaptive, it is rational, it is reasonable.  

But now there’s a twist.  The twist is that some of the categories that we form are categories of people.  We form categories on the basis of… we form categories on the basis of sex, of age, of race, profession, religion, sexual orientation, nationality, and where the person lives.  When you form a category of a person, we have a specific word for that, we often call it a stereotype.  

Now, stereotype may sound like a bad word, but there’s nothing bad about it.  For one thing, stereotypes are often accurate.  Lee Judson finds that when you ask people about their stereotypes of different groups and political groups and ethnicities and genders, people get it pretty much right.  That we’re reasonably good statistical learners, and so we tend to be reasonably accurate.  

Also, stereotypes are often positive, particularly of groups that we ourselves belong to.  Some of the statistical generalizations may be correct and may be positive as some groups have reputations for being smart, for being loyal, for being brave, for all sorts of things that are not at all negative.  And so there’s nothing inherently wrong about stereotypes.  

But there are problems with stereotypes.  For one thing, they’re reliable insofar as they’re based on a sample, an unbiased sample, of the population.  But a lot of the information we get about human groups is through biased sources like how they’re represented in the media.  And if these sources don’t give you an accurate rendition, you’re a stereotype won’t be accurate.  

For example, many Italian-Americans were upset at the depiction of Italian-Americans in a television show, “The Sopranos.”  This is because, if you are in an area where the only Italian-Americans you meet are those you see on TV and those you see on “The Sopranos,” you’re going to think they’re all mobsters.  

Many Jews historically have been troubled by Shakespeare’s depiction of Shylock.  If the only Jew you know is Shakespeare’s Shylock, again, it’s going to be a very bad impression.  And so one problem with stereotypes is while we have accurate statistical mechanisms for taking in information and drawing conclusions from them, often our information isn’t reliable and often this can lead to the formation of stereotypes that aren’t right.  

A second problem is that stereotypes regardless of whether or not they’re accurate can have a negative effect on the people that they apply to.  And this is what the psychologist, Claude Steele, described as stereotype threat.  So he has a vivid example of this.  Here’s how to make African-Americans do worse on a math test.  You have the test and you put on the test that they have to identify their race.  The very act of acknowledging that their African-American when given a test ignites in them thoughts of their own stereotype, which isn’t positive, which is negative regarding academics and that makes them do worse.  Want to know how to make a woman do worse on a math test?  Same thing, get her to write down her sex.  

One recent study found a sort of clever twist on this. The study involved testing Asian-American women.  Turns out, when Asian-American women are given a test and they’re asked to mark down their race, they do better than they would otherwise do.  They’re reminded of the stereotype, but as a positive stereotype and it bumps them up.  You ask them, on the other hand, to mark down their sex, they do worse because they’re women and that’s a negative stereotype towards women.  That’s an example of how stereotypes have a potentially damaging effect on people. 

A third problem with stereotypes is, in some way, our stereotypes of human groups are like our categories of dogs and apples and chairs.  But there’s a way in which they aren’t.  We’re not dogs and apples and chairs.  But we are members of human groups.   

And by definition, any category of human individuals is something you either belong to or you don’t.  It’s either what psychologists call an in group or an out group.  And this fact of how you connect with the category has an effect on how you think of the category.  There’s a lot of evidence suggesting that when you’re a member of the category, you boost it.  You give it higher qualities.  People in your group are smarter or nicer, they’re more deserving and so on.  On the other hand, if it’s an out group, if it’s another category, particularly if it’s a category that you’re in some way competing against, the category gets denigrated.  

We see some vivid historical example of this.  In one study in 1942, Americans were asked to describe the top two features of Russians.  And they described them as brave and hard-working.  In 1948, they were asked the same question.  They described them as cruel and conceited.  The Russians didn’t change, what changed was our relationship to them over the intervening years; they went from being part of a group that we were a part of to the out group.  

More generally, we seem to react in a certain way to out groups where we seem to think of them in general as being less rich, less complicated than we are.  Several studies find that we are less likely to attribute to an out group complicated emotions.  If the out group is somebody we don’t like, that we’re afraid of, we’ll often view them as savages.  If the out group is somebody we kind of like, but we aren’t afraid of, we don’t see them as adversaries, we might view them a children.  None of this is accurate and none of this is moral.  And that’s a third problem with stereotypes.  

The final problem with stereotypes is a moral one.  Even if stereotypes are perfectly accurate, even if they’re accurate summaries of the statistics of a group, there are many cases where we believe that it’s morally wrong to judge somebody based on their group membership.  We should judge them as individuals. 

For all of these reasons, and maybe mostly for the last one, there’s an interesting tension in how we think about other groups.  On the one hand, we want to be consciously egalitarian, consciously non-racist, consciously thinking of individuals as individuals and not letting stereotypes, particularly ugly stereotypes affect our judgments.  And there’s some evidence that we succeed at this.  You look at the statistics, for instance, what you see in this graph, is there are a portion of Americans who say they would vote for a qualified African-American to be President.  And what you could see is, at a certain point by the mid-nineties, just about everybody says, that they would.  And the election of Barrack Obama shows that this wasn’t just people lying when asked questions, it really reflects an honest to god consciously egalitarian viewpoint.  

On the other hand, we also have an unconscious system.  And an unconscious system is more statistics driven, more biased and less sensitive to moral concerns.  So you get a tension between the conscious egalitarian system and the unconscious system, which is often driven by bias.  

So we think the right thing to do is to judge individuals, not on the basis of the groups that they belong to, but as individuals, as individuals in their own right.  And is this something that we consciously endorse?  Most people today or many people today in our culture are consciously egalitarian. 

We want to avoid stereotypes, particularly ugly pernicious stereotypes.  We want to judge people based on their own traits, not the groups that they belong to and this shows up when you ask people.

So for instance, what you see in this graph is a portion of Americans who say they would vote for a qualified African-American to be President.  And what you see is, by the mid-90’s is just about everybody.  An election of a Barrack Obama as President suggests that this really does capture an honestly egalitarian perspective on the part of people.  They’re not just lying when asked questions.  Or consider these data; this is the proportion of Americans, white Americans who would endorse some ugly stereotypes about blacks.  And what you can see is, by the year 2000, they are approaching zero.  And so, this paints a picture of the conscious mind as non-prejudice, as egalitarian.  

But what’s interesting, and perhaps troubling, is that there’s more to our minds than the conscious mind.  We also have an unconscious system that also thinks in terms of categories, that also thinks in terms of stereotypes.  This conscious, this unconscious system is data-driven, is however prone to tremendous bias and it is a lot less sensitive to our moral concerns than the conscious system.  So how do we know this sort of unconscious system exists?  Here we draw upon some very clever studies by social psychologists.  So for instance, in one study, subjects will be in front of a computer screen and they’d be doing some unrelated task and what they wouldn’t know is that faster than they could consciously process, faces were being flashed on the screen.  These were either white male faces or black male faces.  Again, they had no conscious awareness that they were seeing these faces.  

Then they were asked to complete words.  So they might a word, H-O-S, and have to complete it.  It turns out if they’re seeing white faces; these subjects who were consciously unbiased would tend to fill it out with a word like “hospital.”  If they were seeing black faces, they would tend to fill it out with a word like, “hostile.”  

When they were seeing white faces, they would tend to complete it as a word like “hospital.”  When they were seeing black faces, they would tend to complete it as a word like “hostile.”  They would tend to associate these black faces at an unconscious level with malevolent intent; with bad things.  

One striking example of unconscious bias involves being shown these two faces.  And asked who’s more American?  Well, at some level, this is a ridiculous question.  People would laugh when they hear it.  Barrack Obama’s more American because he’s like American.  Tony Blair is British.  But unconsciously, you can ask the same question, you could see how quickly it takes to associate these faces with words like, “American” or “not American.”  And it turns out, based on this sort of implicate unconscious test, people are often more willing and quicker to associate the face of Tony Blair as American than the face of Barrack Obama, of course, because Tony Blair has a white face and Barrack Obama has a dark face.  

Now, one response to these sorts of studies, one perfectly legitimate response I think is say, who cares.  Consciously, we’re egalitarian, consciously we’re non-prejudice, we have these weird, quirky unconscious biases that drive our behavior when pressing buttons and responding very fast.  What difference does it make?  But there’s evidence it does make a difference.  There’s evidence that these unconscious biases play a role in things that matter very much in the real world.  

So consider some studies by Jack Dovidio and his colleagues.  They first did this study in 1989, and what it involved is, you give people resumes of candidates and these resumes have pictures.  And what the subjects and experiment don’t know is they were always given the same resume, but half of them got it with a white person, half of them a black person.  And then they were asked, how strongly would you recommend this person for a job?  Now, if these candidates had strong qualifications, they both would be recommended.  In fact, perhaps the black is a bit more likely to be recommended than the white one.  But when they had moderate qualifications, when it’s a judgment call, the white candidate was statistically more like to be recommended for a job than the black candidate.  Not because these people said, I’m a racist, I’m going to do it this way, but rather they are swayed by this factor that they might not have been conscious of.  

As I said, this was done in 1989.  But they did the same study in 1999 and got the same result.  And they did the same study in 2005, and got the same result.  

Here’s a second sort of study suggesting these racial attitudes really matter.  It was a shooting simulation where subjects are given a gun and they have to decide when to shoot when they see somebody reaching for something.  Half the time they’re seeing a black person, half the time they’re seeing a white person.  Sometimes a person has a gun in their hand, sometimes a wallet or their keys.  Turns out, these subjects again, non-racist, non-biased, at least consciously, were quicker to shoot the black person than the white person.  And there’s some evidence using law enforcement officers that they’re prone to the same bias.  

Not… again, not because they’re consciously racist, but because a split second decision exploits parts of the mind that are unconscious, that are not under your volition or control.  

The final example I’ll give you for why these unconscious racial biases might really matter is a study by Jennifer Eberhart and her colleagues.  They find that once you factor all other considerations, and this is for death penalty cases, considerations like prior records of crimes, the brutality of the crime and so on, you are far more likely to be executed if you look like the man on the right than the man on the left.  The darker your skin, the more likely a jury is to recommend that you get the death penalty.  And this is a case where one’s unconscious biases obviously make a big difference.  

So, we’re at war with ourselves.  We have on the one hand these conscious beliefs about how we think we should think, how we think we should behave.  On the other hand, we have this unconscious system that makes all these sorts of decisions and affects us in ways that we might not know about, we might not be aware of.  The good news is we’re also smart.  And part of being smart means that we can structure our world so that we can make it that unconscious biases matter less.  If we want them to matter less, we can organize things so that they do matter less.  

One example of this, to give you an example of this, I’ll turn not to race, but to gender. Not too long ago, women were deeply underrepresented in symphony orchestras.  And the reason for this, it was argued is because they don’t play as well.  They simply, in a fair and biased fashion they’d been judged and they just don’t sound as good.  But in part, based on these sorts of discoveries, symphony orchestras began to hold blind auditions.  What they would do is they would have the person play behind a screen so that the person listen… so that the judges won’t know if they are listening to a man or to a woman.  Once this was put into place, the representation of women in symphony orchestras shot up.  

It wasn’t that originally these were just sexist, to say, I don’t like women; I’m going to count against them.  Rather, these were perhaps good, non-sexist people, who couldn’t help hearing the woman differently from the man.  And so when you adjust environment, it allows their… them to apply a fair standard, a sort of standard that they would want to apply.  And I like this example because it shows how first, social psychology and psychology in general can shape policy in a good way.  

But second, it shows how we’re smart enough to manipulate the world so that our better selves get to make the decisions.  So that if we think of parts of ourselves as irrational or biased or irresponsible, we can orchestrate things, so to speak, so that our better selves win out.  

The third case study I want to talk about is sex.  And when it comes to sex, considerations of evolution become incredibly relevant.  I think the question of how we evolve and the question of how our minds are now shaped in response to evolution pressure is something that pertains to all of psychology.  It pertains to, certainly, for how we think about human groups, certainly for compassion and morality, and all sorts of other topics I haven’t discussed, like perception and language and memory.  But it’s screamingly obvious in the domain of sex.  

In fact, as soon as you start thinking about our bodies and our brains, you’re faced with a puzzle.  And it’s the sort of a puzzle that can only be resolved in terms of evolution.  And here’s what the puzzle is.  What’s the difference between males and females?  Well, there’s a general answer to this that doesn’t pertain to any particular species that goes across every creature on earth.  

The males are the ones with the small sex cells.  To be a male is to have a sperm, which contains genetic material, and that’s basically it.  The females have the large sex cells. 

The female sex cell, the egg, also contains genetic material but it contains a cover, it contains food, it contains all the apparatus needed to get an organism growing.  

So here’s the puzzle.  You look around most animals, not all animals, but most animals.  And the male is bigger and more aggressive.  So why would the animal with the smaller sex cell tend to grow up to be the bigger animal.  And this has been a mystery for a very long time until an evolutionary biologist named Robert Trivers, solved it.  And he solved it by making reference to the idea of parental investment.  

For Trivers… Trivers defines parental investment as any investment by the parent in an individual offspring that increases the offspring’s chances of surviving at the cost of the parent’s ability to invest in other offspring.  

So given that the organism typically, though not always, grows inside the female, this leads to a difference in parental investment.  A male can ejaculate and then some short periods of time ejaculate again and again and again, each time, theory at least producing a new offspring.  For a female, once she’s pregnant, that’s it.  That’s it for months, is it for years.  She can’t have another child while she’s pregnant.  Often when she’s breastfeeding, lactating, she can’t have another child.  So what this means in practical terms is that children are more valuable for females than for males in the sense of children are… in the sense that females can have fewer children than males.  

What this means is, typically males have less of a parental investment than females.  What follows from this, from an economic point of view, is that males compete with one another for access to females.  Both males and females want offspring, that’s the genetic imperative, but males can be more into number while females can be more into quality.  This leads to competition between males.  And the competition is of two different sorts.  There’s competition male against male, which leads to the evolution of aggressive trades.  It even leads to the evolution of some species with special organs, like the giant horns of some animals that exist for males and not females because they’ve evolved according to this reproductive logic based on the lower parental investment.  

It also leads males to evolve certain traits to attract the attention of females.  Females are the scarce resource here.  And so males compete with one another to attract females.  The most striking biological example of this is the elaborate, glorious plumage of the peacock.

There’s a carton I enjoy here because the peahens are saying to the peacock, “Cut the crap and show us your willy.”  Which I like because it sounds sort of British, but I also like because it nicely captures the evolutionary logic behind what all of this is for.  

So that’s the sort of evolutionary biology 101 when it comes to sex.  What does this have to do with humans?  Well, we see the same sort of differences, the same sort of psychological consequences of this asymmetry in parental investment in human males and human females.  Human males are larger than human females.  Not every human male is larger than every human female, but on an average, human males are quite a bit larger.  Or, many humans, for instance, human males are over six feet tall.  There are very few human females over six feet tall.  Human males are far more violent than human females.  A lot of this has to do with testosterone, but in just about every way you measure physical violence; assault, homicide, rape, and so on, males are by far the major perpetrators.  

Finally, you get to relative choosiness.  Females are, as a rule, more choosy when it comes to short-term sexual partners than males.  And this shows up in a couple of ways, it shows up in prostitution.  So, prostitution is a huge industry in the world.  And with very few exceptions, prostitutes cater to male customers.  Female prostitutes cater to male customers and male prostitutes cater to gay male customers.  

Then there’s pornography.  Now, pornography may appeal to different sexes, some people have argued that romance novels are sort of the equivalent to pornography for women.  But what appeals to men is often sort of images of sexually receptive women.  This isn’t the same as sort of a one-night stand, but is a psychologically vicarious one-night stand, where this image is enough to lead to arousal.  The only thing interesting I have to say about this is a recent study that suggests this is not exclusively a human vice.  So recent study involved showing pornography to Rhesus Macaques, these are a type of monkey.  What they did was… the question was, would these monkeys pay to see porn?  And so you didn’t have a financial system for these monkeys, so they set up a nice apparatus where the monkey… at a certain point, the monkey had a choice, he could either stare at a picture or turn and sip sweet orange juice; monkeys love orange juice.  So the question is, what sort of pictures would they pay, would they give up on this orange juice in order to see?  

And there were two sorts of pictures that they would pay to see.  They would pay to see the behinds of female Rhesus monkeys and they would pay to see the faces of high status male Rhesus monkeys.  Sort of like the equivalent of a Playboy Magazine and People Magazine, suggesting that two of the major human vices, pornography and celebrity worship are in fact not uniquely human.  

Now, you can go on about the differences between males and females in terms of sexual interest and sexual hues and so on, but I want to focus for the rest of this case study on certain things we have in common, which I think are quite interesting.  And one thing that we have in common is an attraction to what we would call beauty.  Certain things are beautiful, certain things appeal to us universally.   Some studies find in the first tenth of a second after looking at a face, you have computed how beautiful it is.  Your judgment as to how beautiful it is.  

Now, one immediate response is, well beauty is in the eye of the beholder.  We different tremendously in what we find beautiful.  Cultures differ tremendously, different times, different places in what counts as beautiful, what counts as sexually attractive.  And that is entirely true; there are interesting and powerful differences.  

But at the same time, there are also universals.  There are certain things that people everywhere find attractive.  And we can use evolutionary theory to makes sense of the sort of things people find as beautiful.  So to some extent, beauty equates to youth.  Hues like round eyes, full lips, smooth tight skin.  Hues like round eyes, full lips, tight skin are considered beautiful most likely because they’re **** that the person is young, is able to have kids, has many years ahead of them and so on.  

We are drawn to features like absence of deformities, clear eyes, unblemished skin, intact teeth, and average faces.  And you might think, average faces?  That’s strange thing to put in beautiful, as a category of beautiful.  But it turns out average faces actually look really good.  And there’s different hues as to why that’s so, but one plausible explanation is, if you’re face differs from everybody else’s face; it’s most likely due to something which isn’t good.  There’s more bad things that can happen to your face than good things.  And so something that deviates from the average is often something which isn’t normally viewed as attractive.  So what an average face does is it gets rid of all of the things that are unusual and people tend to find it quite attractive.  

Now, an immediate response to all of this, to say well, typically psychologists get blamed for studying… do all their research based on university freshman, in fact, freshmen taking intro psych courses.  How general is this?  How much does it apply?  But there’s a lot of evidence that these attractiveness features are human universals, there are studies that are done across cultures.  And most interesting to me at least, is studies done with babies.  So it turns out, it’s not just you and me that can tell one face from another, it’s actually babies.
Now one accusation that always comes up in these situations is, who did you get this data from?  And in fact, psychologists are often guilty of collecting data from 24 university freshmen and then saying that these conclusions apply to all of humanity, but not in this case.  In this case, studies of human attractiveness have been done cross-culturally and you get pretty much the same findings wherever you go.  Again, there’s some interesting differences, but these universals seem to always be attractive.  The work that’s most exciting to me along these lines is actually done with babies.  So adults can rank faces as attractive or unattractive, but you can also see what babies think about faces.  And it turns out, using babies looking time as a measure for what they like to see.  So how long will they look at a face?  It turns out that babies preference for attractive faces match pretty well adults preferences for attractive faces. 
So for instance, in some wonderful work by Languar[ph] and her colleagues, she would show different degrees of averageness across faces, composites of more and more people.  And when a face was very average, a composite of as many people as she can get, babies prefer to look at it over less average faces.  Matching how adults judge faces and suggesting that some gut feeling about what makes an attractive face or an unattractive face isn’t just due to culture, it’s not just due to learning, but it’s part of our hardwiring.  It’s part of an evolved system, part perhaps of the sort of Swiss Army knife we start off with for dealing with people and making judgments as we go through the world.
So average faces are attractive.  You can see this in these faces are not the faces of real people, these faces are computer composites of multiple people and they are not bad looking, but you can get better than average for both males and females.  For females, many people will judge a face better than average if it’s feminized.  If you take the features that define a face as female and you exaggerate them, as in the picture on the right, it tends to look a little bit better than your average female face.  For men, you could do the same thing.  

And this is the wonderful work of Victor Johnston, where he found that you could take faces and take your average male face and turn it into testosterone man, which is the face that you’re looking at on the left.  

It turns out that women’s responses to testosterone man differ according to whether or not they’re ovulating.  So if a woman is ovulating, she is more likely to find this manliest of man face attractive, while if not, she tends to go back to just find average man more attractive. It does suggest that our sexual psychologies connect with our reproductive preferences in all sorts of interesting ways.  

Now, I’ve talked so far about attractiveness from a very narrow evolutionary perspective.  Looking just at those features, we can see in how that affects your judgment of how attractive somebody is, but there’s a lot more to looking good than how you look.  There’s a lot of really nice demonstrations that what you think of a person, what you believe about a person affects how attractive you think he or she is.  

So, these are two faces we’ve used in our experiments, these are judged by people in the absence of other information as a pretty attractive man or a pretty attractive woman, but it turns out, how attractive you find them, depends on your beliefs.  You probably think the person on the left is male and on the right is female.  If you find that this belief is mistaken, that the one on the left could be female or the one on the right is female, it will change how attractive you find them, it will change your sexual response to them.  It’ll change your sexual and romantic response if you discovered that they’re much younger or much older than they look.  It will change your response to them if you were to discover that you were actually looking at a disguised version of your brother or your sister or your child.  That’ll switch your sexual desire right off if you believe that this is kin because we have a hardwired system that says, you could think of you kin as extremely attractive, but you won’t tend to be sexually aroused by them.  

More generally, we’re strongly affected in our judgment of how attractive a face is by who we think that face belongs to.  This points to a general fact about the psychology of sex and love, which was pointed out by George Bernard Shaw, who defined love as a gross exaggeration of the difference between one person and everybody else.  And I want to give as an illustration to this a somewhat unusual case, but I think it makes… I find it persuasive.  It’s a story of a woman with Capgras Syndrome.  

Capgras Syndrome is a very rare neurological disorder where you develop a very specific delusion.  You develop the delusion that the people you love most in the world have been replaced by exact duplicates.  Now, often the results of Capgras Syndrome are horrible.  People have murdered their husbands, their wives, their children, their parents believing that they were imposters, they were robots or they were spies or they were aliens.  But in at least one case, the result of Capgras Syndrome turned out to be quite nice.  This was a case reported in 1931.  And according to the description of the case report, in 1931, researches described a woman of Capgras Syndrome who complained about her poorly endowed and sexually inadequate lover.  She was happy to report that she had discovered that he possessed a double who was rich, virile, handsome and aristocratic.  Of course, it was the same guy, but she was seeing him through different eyes.  

It’s reminiscent of a story by Isaac Busheve[ph] Singer about a man who lives in a small town and he is bored of everybody in the town, he’s particularly bored of his wife, who he’s seen for so long.  He’s so sick of her, he decided he’s going to leave and never come back.  Find new and exciting people.  So he leaves the town.  But this being an Isaac Busheve Singer story, something incredible happens.  He gets turned around and ends up marching back into his old town, but he’s confused.  He thinks he’s going to an entirely different place with all these different people who just so happen to look and behave just like the people he had left.  He sees his wife, he thinks it’s a woman who looks so much like his wife he had left and falls passionately in love with this new person.  

I’ll say one last thing about our responses to people’s faces.  It turns out that how attractive you find a face is critically dependent on how much you like the person.  The more you like somebody, they better they look to you.   This is why spouses in happy marriages will honestly find their husband or wife far more attractive than anyone else finds them.  And this is true more generally.  

In a classic study, David Bus tested people from 37 different cultures around the world and asked who is your perfect mate?  He was largely looking for sex differences in these studies, and he found them.  He found all sorts of differences in what men were looking and what women were looking for.  But he also found one similarity, one thing… on way in which men and women were alike.  And this is that, for both, the number one quality people were looking for in a mate was kindness.  All of this in the domain of sex supports a moral from Shakespeare, which is that love… which is, as Shakespeare put it, “Love looks not with the eyes, but with the mind.”  

What I’ve done is I’ve very briefly talked about three case studies in the domain of psychology.  I talked about compassion.  I talked about racism and I’ve talked about sex.  In the course of this, I tried to illustrate certain themes in the study of psychology in general.  And in fact, I started by listing six domains of psychology.  And I want to go back and just very briefly point out how these domains connect to what we just talked about.  

Neuroscience, I started by talking about the baby’s brain and gave that as a starting point for the question of the development of compassion, the development of these other traits.  But every domain of psychology, every aspect of mental life is caused by our physical brains.  And in fact, in all of these domains I’ve talked about, compassion and moral psychology and more general, race and stereotyping and thinking about groups, and sex and sexuality, people have used the methods of neuroscience, including brain imaging methods like FMRI to better understand the processes going on.  To better understand how the mind works in these domains.  

I’ve talked about development and I focused mostly in development on the first case study on compassion, but of course there’s a huge amount of very interesting research on the development of our understanding of groups asking the question, for instance, are young children racist?  Do young children have complicit biases?  And of course in the development of romance and sexuality, how does the mind of a child before puberty differ and how much is it like the mind of an adult after puberty and how did these differs take place?  These are extraordinarily interesting developmental questions.  

All three domains connect to social psychology and cognitive psychology in clear ways.  They are all questions about social psychology, they are all questions about dealing with other people; how we deal with and make sense out of other people.  And they all connect to questions of cognitive psychology, like the perception of faces, the formation of categories, the comprehension of stories; those are all central parts of cognitive psychology and central to understanding the domains we’ve talked about here.  

We’ve talked about evolution, particularly again, in the case of sexuality.  But of course, the evolutionary psychology of morality and compassion is a fascinating issues connecting it with research done with other primates, our evolutionary relatives like chimpanzees and monkeys.  Similarly, there’s a lot of exciting work on extent to which other primates make sense of other groups.  There’s work, for instance, done by my colleague, Rory Santos at Yale, on the extent to which other non-human primates have races in the sense that they think of this group as different than that group and that have implicit biases that extend to one group and not to the other.  

I’ve said the least about clinical psychology.  I brought up on case of Capgras Syndrome as an exotic case of clinical psychology, but I haven’t talked about it, and this is a shame because there is so much that could be said.  Clinical psychology is extraordinarily interesting and also connects to each of the domains that I’ve talked about.  People are interested in the psychopathology related to sexuality.  They’re particularly interested in the psychopathology in mental illness in the domain of morality because this connects to one of the most troubling and one of the most interesting questions in clinical psychology, which concerns the psychopath.  

There are some of us, apparently, who don’t have consciences, who don’t feel compassion, who will destroy other people’s lives out of malice or self-interest or simple boredom.  And the question of where psychopaths come from, what’s the precise nature of what’s going wrong with them.  Most of all, what can be done about them are issues of extraordinary interest.  

I want to end on two notes.  The first is a note of humility.  I think psychologists and more generally, neuroscientists and cognitive scientists have learned a lot about the mind.  But we have a huge way to go.  The most clear thing that we don’t understand is the problem with consciousness, the problem with experience.  We understand… we have some glimmering of how physical brain can process information, can recognize faces, can make judgments, can form categories.  And in fact, we build machines, computers that are physical machines that can do these things.  There’s no great mystery here.  But we’re left with what the philosopher, David Chalmers, has called “the hard problem with consciousness.”  The hard problem of consciousness is how a physical brain,  and it looks like a lump of meatloaf, can give rise to pain and pleasure, give rise to humiliation and lust and meaning and purpose.  How these things can come from a mere physical objects.  And we struggle to explain it.  This is a problem that goes through every aspect of psychology.  

I’ve said before that I’m a developmental psychologist. I’m fascinated by the minds of children.  This is my son, Zachary, when he was two-years-old.  And I think as a developmental psychologist there’s some things I understand about Zachary.  I understand his developing knowledge of the world, his growing grasp of language.  How he makes sense of objects and people.  But I don’t understand what it’s like to be a two-year-old.  I don’t understand his experience, his phenomenal sense of himself.  And I don’t think any psychologist understands that.  I think we’re at a loss when it comes to this very, very hard problem.   

But the second theme is optimism.  I think we’ve made huge progress in understanding the mind.  I think over the last many years, psychologists along with neuroscientists and cognitive scientists and philosophers have learned a huge amount about how the mind works and I think there is no reason to expect this progress to stop. I think that in the end, the most important and intimate aspects of ourselves, our understanding of other people, our conception of human groups, our conception of ourselves, the decision we make, the emotions we feel, our sense of right and wrong, how we know what’s right and know what’s wrong.  And the forces that make us act upon is the most interesting and intimate aspects of ourselves will be explained through the program of scientific psychology.  They will be explained through constructing scientific hypotheses and testing them.  

They will be understood through neuroscience.  They’ll be understood through computation.  They’ll be understood through evolution.  And together, we will come to some real insights about how the mind works.  

Now, some people might find this a scary prospect.  I know that there are some people that worry that a scientific perspective of the mind takes away from us somehow.  It diminishes us.  It makes us less than what we are. I don’t agree.  I have the opposite reaction, which is that as the more you understand the mind from a serious scientific point of view; the more you come to appreciate its complexity, its uniqueness and its beauty.  

Thank you.