Dr. Helen Fisher on How Brain Chemistry Determines Personality and Politics

Is the libertarian mind a product of elevated dopamine and testosterone?


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If libertarians are bold, impulsive, quick witted, adventurous, analytical, and willing to ignore social norms, is that because we have especially active dopamine and testosterone systems in our brains?

That's the hypothesis of the biological anthropologist Helen Fisher, who has developed a pioneering framework for classifying human temperaments. She categorizes her subjects by having them take a personality test that's used by online dating sites and to better link potential mates. To date, her questionnaire has been taken by more than 14 million people in 30 countries.

Barack Obama, according to Fisher, is high in dopamine, accounting for his optimism, and also in estrogen, which explains the Oval Office rug covered in inspirational quotes. Mitt Romney is in some ways the opposite of a libertarian, high on the serotonin scale, which accounts for his respect for authority, rigidity, and loyalty.

Fisher is a senior fellow at the Kinsey Institute and she's the author of six books, most recently Anatomy of Love: A Natural History of Mating, Marriage and Why We Stray. She spoke at the Reason Foundation's annual donor weekend in West Palm Beach, Florida.

Edited by Ian Keyser. Intro by Todd Krainin. Cameras by Meredith Bragg and Jim Epstein.

"Sphunx" by Sk'p is licensed under CC BY NC ND 3.0

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This is a rush transcript—check all quotes against the audio for accuracy.

Helen Fisher: Anyway, I study the brain. I and my colleagues have put over 100 people into a brain scanner and studied the brain circuitry of romantic love, people who have just fallen happily in love, people who've been rejected in love, and people who are in love long-term. It's possible to be in love, not just loving, but in love long-term but you got to pick the right person. In 2005, a couple of days before Christmas, my phone rang in New York and it was They called me and they said they wanted to meet with me two days after Christmas to talk. Nothing happens in New York City at Christmas-time so I was astonished and I walked into the room with them and 11 people piled into the room and I had no idea who they were. I thought maybe this was a think tank and there were other academics, I didn't know.

Anyway, in the middle of the morning somebody, it ended up being the CEO, turned to me and he said, "Why do you fall in love with one person rather than another?" I said, "I don't know. With all kinds of cultural reasons that you do," but I began to think people will say we have chemistry or we don't have chemistry. Could it be that nature has evolved some natural personality styles that are drawn to one another? I began to think to myself that I would look into the biology of personality and see if I could understand the human mind.

There's two parts of personality, there's your culture, everything you grew up to believe and say and think, and there's your temperament, your biology, your predispositions. I study your temperament, your nature. Epigenetics is the most important thing actually that's ever happened in my life. It's the combination of how these temperament and culture interact with one another, but basically I'm going to talk today about your temperament, particularly the temperament of the libertarian mind.

There's all kinds of things that evolved. We now know that a good 40 percent to 60 percent of who you are comes out of you biology, and one of them is how you feel intimacy. Women tend to feel intimacy from face to face talking. We swivel until we're face to face, we do what's called the anchoring gaze, and we talk. That's intimacy to women. It probably comes from millions of years of holding your baby in front of your face, cajoling it, reprimanding it, educating it with words. Men tend to get intimacy from side by side doing. When he looks up he'll look away. They can watch a football game all Sunday afternoon and say almost nothing to each other, and get a great deal of intimacy out of it. It probably comes from millions of years of sitting behind a rock on the grasslands of ancient Africa trying to hit that buffalo in the head with a rock. You can't be talking to your neighbor when you're doing that kind of job.

The problem of course is this, they both are different. I'm in the business of trying to find those differences. I've never met two people who were alike. I'm an identical twin, even she and I are not alike, entirely alike. She's actually a hot air balloon pilot, I'm an anthropologist. She takes people up in a tiny little basket, I walk on major podiums and talk about the evolution of adultery. They're very different things but they both require a certain personality style. Anyway, people are different and in fact there's a lot of new data that a political scientists now think that politics is at least 40 percent to 50 percent comes out of your DNA, and they've actually coined a new term called genopolitics.

That's my hypothesis began with this morning at the, and I decided I wanted to find out if we're naturally drawn to one person rather than another. I decided what I would do is go through all of the academic literature looking for any trait at all, linked with any biological system. For example, SNPs, single-nucleotide polymorphism, there's a lot of genetic differences and I would collect data on that. L-DOPA, if you give L-DOPA to a Parkinson's patient you're driving up the dopamine system in the brain, and with that it's actually linked with creativity. I wish I had it, I've never been able to find it since, but I was once talking with a woman who studied this and she was studying a woman who had Parkinson's and that woman was drawing stick figure dogs. Then after giving this woman L-DOPA she was literally drawing dogs that looked like Rembrandt dogs, it was quite remarkable.

Antidepressants, particularly the serotonin boosters, Prozac, Paxil, Lexapro, all of them, they actually reduce curiosity and exploratory behavior. LSD dries up the serotonin system in the brain, the serotonin system is linked with religiosity. This is one reason that people will get a religion high, I'm told, when they take that drug. Estrogen replacement really helps with the memory, there's a lot of estrogen receptors in the hippocampus linked with memory and if you take ERT, estrogen replacement you're likely to actually to boost memory and get greater linguistic skills. By looking at all of these things I began to find that there were four basic brain systems that was each one of them linked with a constellation of personality traits.

Now there's all kinds of systems in the brain, most of them keep the heart beating or the eyes blinking, they're not linked with personality traits. These four are all linked with each one of them a constellation of personality traits. What I decided I would do is make a questionnaire to see to what degree you express the traits in each one of these four basic systems. Now for example I know that people who are very expressive of the dopamine system tend to be unpredictable, so I created a questionnaire I find unpredictable situations exhilarating. I figured the high dopamine type would say yes, I do, I like them. Should behave according to established standards proper conduct. People who are very expressive of the serotonin system I figured would be particularly gravitate to that and say they strongly agreed and on and on. Competitive conversations is linked with the testosterone system, and I knew from other academics that people who they carry their emotional feelings with them for hours, days, weeks, or even months or years, link with the estrogen system.

By constantly putting questions in, taking the ones out that don't work, I established a questionnaire that has now been taken by 14 million people in 40 countries. About 30,000 people take it every two or three weeks and so I keep on perfecting it. At the end of this I want to give you the most recent and actually better version of this questionnaire because my hypothesis is that you are all going to be quite expressive of the traits in the dopamine system and in the testosterone system. You're not going to have any serotonin in you at all, it's my guess, and some of you are going to have some estrogen, we'll see about that.

Anyway it's a nice scientific experiment for me and a hypothesis. This is only one person. When you take my questionnaire, as Katherine said, we're not only just one thing, this is one of the problems with all of these personality questionnaires, the brain is not buckets, the brain is systems, they're constantly interacting in all kinds of ratios. This particular individual is very expressive of the traits in the dopamine system and in the estrogen system. As I say I've got 14 million of these things and I'm studying people. Because I was working with a dating service I had to name them and so I named people who were very expressive of the dopamine system explorers, academic term is curious energetic. Those people very expressive of the serotonin system I called builders, not a great term but I'm stuck with it now. Cautious, social norm compliant, that's not you? Those who are very high of the testosterone system I call them the director, analytical and tough minded. Those particularly expressive of the estrogen system I call the negotiator or pro-social and empathetic.

This next slide is only for me. It's one of the most important things in my life and it is because what I did is after I made this questionnaire from looking at the brain literature, I made the questionnaire, and then I went on to do two brain scan studies to prove that the questionnaire actually measures what I say it measures. There's no other questionnaire in the world that has been able to do that because the Myers-Briggs and all the rest of them they started from linguistic studies, and you can't go from linguistic studies to make a questionnaire and then go back to linguistic studies to prove it. I've been able to prove that you are very expressive of the dopamine system on my questionnaire, you're going to show more activity in the dopamine system in the brain, etc., etc.

I finally, having looked at this, and this is only the second time I've ever shown this slide, it only dawned on me very recently is what I've really stumbled on is two basic aspects of all living mammalian, avian, reptilian creatures. The degree to which an animal expresses the trace in the estrogen versus the testosterone system and the degree to which they express the traits in the dopamine versus the serotonin system. What I call the stay and go. You can see a fish, the bigger fish comes by and the fish will step back into its hole because it's going to stay. Another fish is going to come out and take a look at the other fish and he's going to go. It's this push pull of two basic biological systems of staying, of protection, of tradition, of conservative, as opposed to curiosity, creativity, and exploration.

I'm going to maintain that you are going to express a great deal of activity in the go system, the plasticity system and a great deal of expression in the male system. There's a lot of women who have high testosterone and I say that, I'm going to show you why, because I think these people are logical, and the one thing I do find about libertarians is that you're logical. I would imagine there's going to be some libertarians who fall within here and I'll be surprised if there's anybody in the room who's high on the stay system, the serotonin system, but we'll see.

Anyway, I'm going to go through these four broad styles of thinking and behaving linked with the dopamine system. The academic term is they're sensation seeking, novelty seeking, risk taking, they're willing to take a risk, they're curious. As I say, I've got 14 million of these things. They're the most curious, they have the most interests, they're the most likely to make it through school, through college and graduate school. They make the most money, they also lose the most money because they're so impetuous, energetic, restless, exploration, and it's not just jumping off mountains, it's mental exploration also. Reading, the opera, the theater, movies, conferences, etc., etc. They happen to be enthusiastic and optimistic. Actually I think that Obama has quite a few of these traits also. After he first won the first election The Onion, the humor magazine, the lead line was Black Man Given Worst Job in the World, and indeed I think he was optimistic about it. I don't know if he's optimistic today but I would imagine that he's more optimistic than he should be.

Independent, that's you, that's your middle name is independent. Self-reliant, spontaneously generous, these people will walk into a bar and buy everybody a drink, spontaneously generous. Mentally flexible and open minded, I'm thinking that that is you. The biggest part of it is idea generation, the dopamine system is linked with idea generation, verbal and numeric creativity. They're also tactically intelligent, they're fast, most of the people on TV are going to be high on the dopamine scale. You got to be quick in the media and I think the vast majority of them are going to be high dopamine.

They can also be susceptible to boredom, that's me. I don't get onto an airplane without at least … I was thinking of what I brought down here. I brought three book. In case I'm on that tarmac for one month I got something to do. Reckless, they can be reckless. Unreflective, they look out not in. I give a lot of speeches to the therapy community, couple therapist particularly and once I said to myself … I mean there was about 600 people in the room and I said, "Well you know I'm not interested in who I am." Some guy from the back of the room screamed, "You want to talk about it?" I didn't. They can be manic, insincere, opportunistic, and unpredictable.

I did a study of 178,000 people. It comes out of the 1930s, it's called the Lexical hypothesis, and that hypothesis is that you say words that reflect who you really are. I wanted to know whether you use words that reflect who you are biologically. I collected 178,000 of these profiles from and another site, and I wanted to see people who are very expressive of the traits in the dopamine system, the top 10 words they use in describing themselves and what they're looking for. Adventure, venture, spontaneous, energy, new, fun, traveling, outgoing, passion, and active. One of the things that I say when I talk to a business group is listen, not only to the content of a person's conversation but the words they use as they are expressing that conversation. It can say a great deal about the basic wiring of your brain.

Richard Branson's a good example. I've always thought rules were made to be broken. I don't know how libertarians feel about that but I've always had the urge to live life to it's full. He ran across the Atlantic in a hot air balloon without knowing how to sail it. They all had to jump out over Ireland and the other guy jumped out first and he's floating around in the sky in a small basket for God sakes. Lang Lang the concert pianist, flair, dazzling, charisma, bravado, daredevil, extremes, a very different man, very different part of the world he grew up in, a very different occupation but the same basic brain temperament. Certainly Peter Thiel, a real entrepreneur. One of the first outsider to invest in Facebook. Bitcoins, now that's out of the established coinage system. Funds all kinds of radical new ideas. Really supports any kind of individualism, that's all the kind of thing that you would see in a high dopamine temperament.

He was also a math whiz and a chess prodigy and that's testosterone. If I don't know the man at all, also he's got a face that shows quite a bit of the testosterone. The very square jaw, the high forehead, the heavy brow ridges are all built by testosterone. If I had to guess, educated guess I think, he would be very high on my scale of the dopamine and testosterone scale, and certainly a libertarian.

In love these people go for people like themselves. They want somebody who's going to leap off the couch and go over to the Met at 7:30 and try and get into the opera that night. They get bored easily and they want a partner who will play ball with them. The people who are very expressive with the serotonin system, this I think is your opposite, it's my hypothesis anyway, we'll find out when you take my questionnaire. This is straight out of the brain. We know the genetics of observing social norms, they follow the rules, they like the familiar, they go to the same place every summer for summer vacation, they go to the same restaurants in the evening, they hang around with the same groups of friends, they're cautious. They're not scared, the academic term is harm avoidance, they're not scared. I've got a friend in New York who's very high on the serotonin system and when we walk towards the corner of the street he steps back. I'm likely to run across the street and he steps back.

Self-control, this is why you take Prozac or Paxil or Lexapro or one of them. You're driving up the serotonin system and creating the calm, the self-control. They're also modest people, and in fact when I work with and I work with some of these people one of the things you've got to do in love is not be too modest. Courtship is not about honesty even, it's about winning and they can be too modest. They like plans, rules, schedules, they follow the rules, they're orderly, they're persistent, they're very good managers by the way. Concrete thinking and I learned my lesson with this one. I had written a book on this for love and it's called Why Him? Why Her?, and I happened to be in Seattle. There was a woman interviewing me for the Seattle Times or The Washington Times, whatever it is called. I was telling her about my hypothesis and these personality styles and love and everything, and the more I spoke to her the more I realized that she couldn't stand me, she really couldn't stand me.

I became more flamboyant, that's what I generally am, and it didn't work at all. The following morning I read the newspaper and I was right, she couldn't stand me, and I went to the airport. On my way to the airport in this taxi cab I said, "Helen get with the program here." What I should have done with this woman is poured details on here, the Cronbach's alpha, the eigenanalysis, all of the math of everything. I should have poured the details on her and she would have liked me. It was at that moment that I began to realize something that I've long held, which is I don't believe in the golden rule, do unto others as you would have done unto yourself. I believe in the platinum rule, do unto others as they would have done unto themselves and you will win.

They're literal, detail oriented, I like details but they got to add up to something. They like details just for details. Very good with numbers, got to belong, you take Prozac or Paxil and you end up having more close friends. Respect authority, follow the rules, religiosity is in the serotonin system, and loyal. Every time I do the math these people have got to have loyalty. I don't remember the question on the questionnaire at the moment but you'll see it soon enough, but it's something like would you rather have interesting friends or loyal friends? Now we all want interesting friends and we all want loyal friends, but this type cannot tolerate unloyal friends and the other three types, including me, cannot tolerate uninteresting friends. It's a real math difference in hundreds of thousands of people. Conscientious, dependable, on the downside they can be close minded, controlling, that's a big one controlling, rigid, stubborn, and moralistic.

Top word they use is family, honesty, caring, morals, respect, loyal, trustworthy. I did that one twice, and values, really big on the word values. Mitt Romney I think is the perfect example. For Newsweek before when he was running against Obama, I certainly read his book, I don't know if you did. Anyway he's an orderly guy and I read an awful lot about him. Loves daily schedules, loves them, you can't be a Mormon without respecting authority, it's a very hierarchical religion, religious guy, etc. You can also see the testosterone in him, the heavy brow ridges, high cheek bones, very squared jaw, and the high forehead. Once again but very high I think on the serotonin scale.

Hu Jintao, former President of China, the current one I think is very high testosterone. This guy I think is very high serotonin. By the way, there's a gene in the serotonin system linked with social norm conformity. Where in the world do you think that that gene is most prevalent? Shout it out. China, China and Japan. I've been in, I'm sure you have too, I've been in the train station in China and you can see 40 little boys lined up waiting for the train. You can't get 40 little boys in New York City to line up for a train. It's the high serotonin style. I think Mike Pence is very high on the serotonin scale. These are the words he chose, that he's a principled conservative and a common sense conservative. I don't think Mr. Trump was going to say he's a common sense conservative. Controlling guy, wants to restrict a lot of things, Evangelical Christian, etc., and real nationalism. Very high I think on the serotonin scale.

High serotonin people are also drawn to people like themselves. I think Mitt Romney and Ann are really a perfect example of serotonin meets serotonin. The third of the broad styles of thinking and behaving, don't forget we're all a combination of all of them, high testosterone. These people shoot for the stars, analytical, logical, good at math, engineering, computers, or music. Music, I think Beethoven was high on the testosterone scale. Music is very structural I'm told. I'm high dopamine, I don't hear any structure at all, I'm just swinging to the beat, but the bottom line is these people see the structure of music. Experimental very definitely, inventive, rank oriented. You inject testosterone into a dove or a lizard and they're going to fight, they're going to be in a fight for rank. High testosterone people indeed are a very rank oriented, and in fact it's called dominance matching and it's an academic term.

I learned my lesson, one night I was at a club in New York City, it was a black tie event and I was standing there with four men. One of them was a guy from The Wall Street Journal and he was taking me to the cleaners, he was dining out on Helen Fisher, just dining out. The other three were watching. I got smaller, and smaller, and smaller, this two basic animal postural gestures throughout the animal kingdom looking little and looking big, it's called crouch and loom. Lobsters will do it, they'll walk high on their walking legs. Guppies will put their fins out and arch their backs to look big or they'll look little. I was getting smaller and smaller, this man was going, attacking me, and all of a sudden I turned around to him and I said something vicious. I don't remember what it was, but it was also funny.

All of us went like that, it was called a barred tooth display. Chimpanzees do it too, you do it when you're just terrified. We all stood there looking at him and I thought to myself, "Oh if he thinks like a woman he's never going to forgive me. If he thinks like a man I will have matched him in dominance and he will like me." This long pause and then he turned, he throws up his hands says, "Helen," he starts to laugh, that let all the rest of them laugh, and that man has respected me from that day to this. One of the things that I say to people is with this kind of a person attack back. It's a little hard to do. The second in command at, she's the only person that did take my advice, she's the only one that attacked the CEO. This was a guy who ate rocks for breakfast, this guy and eventually she was the only person that made friends with him. Actually she finally got his job so that did it.

Emotionally contained, I have a girlfriend who said to me some time ago, she told me the story about her husband. She said to her husband, she said, "Sweetheart, you haven't told me that you loved me in a month." He said, "I said that last month and nothing's changed." Emotionally contained, decisive, bold, tough minded, and direct. These ones get to the point. On the downside they can be uncompromising, impatient, demanding, mind blindness, it's an academic term for the inability to read other people, read posture, gesture, tone of voice. In fact that may be the evolution of why women cry more than men do. We both cry but women cry more tears and it may be just saying, "Hey buddy, got to get the drift here, there's something going on." They're less sympathetic. Americans love empathy, but when you really think about it for millions of years, I'm an anthropologist, for millions of years on the grasslands of Africa men had a job that did not require empathy. They had to catch that baby gazelle, slit its throat, and bring it home for dinner. They couldn't start weeping and let it go or bring it home as a pet.

There's different kinds of altruism. Men will rush into a burning building and save people that they don't know. Women won't do that, so it's not that men aren't empathetic, we got to break down the understanding of what that word means and under certain circumstances. Men are going to be much more, what we would call empathetic, or maybe it's perhaps just heroic. Nevertheless, on scales of empathy the high testosterone … As they get older levels of testosterone actually go down and men become more and more empathetic. Women become more tough minded after menopause as estrogen goes down, unmasking levels of testosterone. These are volatile systems, but on average high testosterone type tend to be less empathetic, and aloof, they do not suffer fools gladly. They get bored easily with it.

Top words they use, a lot of different kinds of intelligence but this is the sort of knowing a lot about a subject, debate, geek, nerd, ambitious, driven, politics, challenge, and real. They're the least likely to be religious or even spiritual. Steve Jobs is a perfect example. You can really see the testosterone in that face. The high cheek bones, the very squared jaw, the heavy brow ridges, and the high forehead. Self-discipline, brash, prickly, demanding, brutally honest, these are the honest ones, perfectionist, exacting, demanding, impatient, and focus. All very high testosterone traits. Margaret Thatcher, they called her the Iron Lady for some reason and here we got the epitome of it. I've never shown that slide before. I don't generally discuss psychotic people, but he's testosterone on steroids this guy. I could say a lot more about him but we all could.

In terms of love they go for their opposite. High testosterone people tend to go for the high estrogen type. In business I would guess that they probably are much more comfortable with people like themselves. High estrogen, the last of the four broad styles of thinking and behaving. Plato called them philosopher kings. I coined that term web thinking. In the womb estrogen and testosterone wash over and build the brain. What estrogen does, if you got the genetics for it, it builds more pathways between the two sides of the head and more pathways between the front and the back. It's a better connected brain. It's not to say that it's any smarter, it's just able to pull out data almost simultaneously from different parts of the system. I call it web thinking. It enables people who are high estrogen to be very good at contextual holistic and long-term thinking.

They're imaginative because they can create a whole pile of different concepts, very good at tolerating ambiguity, which I think libertarians are extremely good. I think this is actually one trait, it's my hypothesis, that libertarians would excel on, and mental flexibility. Very good at what we call executive social skills, linguistic, reading posture, gesture, tone of voice, etc., intuitive. They can get into your head. We now know the biology of intuition. It's not magic, what they're doing is they're pulling data out all at the same time and so they're leaping over sort of systematic thinking to come of the global concept. A Nobel Prize was won for understanding that. Empathetic, nurturing, trusting, that's a strange one trusting. Anthropologists have long wondered why could we have evolved the concept of being trusting? You trust the wrong person and you're screwed.

The reason I like that so much is because you can begin to see that this type of person who's trusting is also good at reading posture, gesture, tone of voice, thinking contextually in the long-term, tolerating ambiguity in the system, and getting into people's heads. You can begin to see how a constellation of personality traits can evolve together. Introspective, everything has meaning. Just the way he slices that lemon for the drinks tonight means we're not having sex tonight. Everything has meaning and you've got to be aware of that when you're working with them. They're seeking, they're going in. They seek harmony, tend to be agreeable, emotionally expressive, and what I call diplomatic intelligence. On the downside they can be scattered, they don't think they're scattered, but the collective data from here and there and the rest of us think they're scattered.

Indecisive, as I say I have an identical twin sister, I'm very high on this estrogen scale. Where do you want to go for dinner? I don't care we can go here, we can go. Well where do you want to go? We can go here, we can go here, we can be really … I'm not in my work but very indecisive otherwise. Placating, they want to please, they want to level the playing field. Ruminating, they can think over and over and over about something. There's some sort of business meeting and there's a fight during the business meeting and afterwards all the men go out and have a beer and the women go home and think about it for three weeks, ruminating. Gullible, they can be too trusting, hypersensitive, backstabbing, not going to hit you in the fact, going to stab in the back, and unforgiving, they remember. High estrogen remembers what you didn't do five Christmas' ago. They remember. I think it's a bit of a blight for both sexes, and effusive.

Top words is passionate, real, heart, kindness, says reader, they're the big readers of the world learning random, they like random. High testosterone doesn't mind random as long as they can make a pattern out of it. High dopamine can do random, but the high serotonin needs order, they need order. Obama I think is very high estrogen. In the Oval Office he had a rug with inspiration quotes on it. My goodness, that's high estrogen. He's about to do a TV program. I was reading this on the plane and I can't remember, I should have read that this morning, it's something almost a self-help kind of program, that's high estrogen guy. Bill Clinton, whole world knows he can't stop talking. He's got good people skills, his books I don't know. His book is something like 963 pages. I think it's important to have a synthesizing mind, that's what he said. Emotionally expressive, he feels everybody's pain, very soft face of high estrogen.

We've been wondering for some time when we are going to have our first female president. I think we've had our first female president. Certainly Charles Darwin, that man put together all living things and also very dopamine guy, went around the world for five years, etc. Very different people, very different backgrounds, very different interests, but the same basic temperament.

The high estrogen tends to go for the high testosterone kind of person. This is a map I've never shown, I mean I've never gotten it published, of America's … As I say I've got 14 million of these things. High serotonin I know that should be red but it's royal blue because I think that's the appropriate color, all over the South and Midwest. They are all much more republican, as I say I've got all that data, and much more religious. High estrogen is in the Northwest and Northeast where most of our universities are, which is educational and reading. Everything that's loose rolls into California, that's the high dopamine. All around Washington is testosterone where they are trying to run the world, or in Alaska where they're trying to shoot the animals, or Nevada where they're gambling, so it's a very high. You can begin to see not only how America sorts itself biologically, but actually if I were to look at the world it would sort it's own.

I'm very interested in migration patterns now where people will go to areas where people think the way they do. You're going to see pools of genes, of certain biological and temperament styles. I think these things all evolved together. There's a hunting and gathering group. As an anthropologist we think about early hunting and gathering bands were about 25 individuals, maybe 10 or 12 children, and 10 or 12 grownups. They're all going over a hill and they suddenly see some mushrooms. Well you can't have all the high dopamine people say, "Ah, let's try the mushrooms." You're going to have some of the high serotonin people say, "It's not in our tradition to try these mushrooms." You got to have some high testosterone people who say, "Let's have an experiment. Let's feed the mushrooms to the dog and see what happens." You got to have some high estrogen people who say, "Let's sit down and pool our data about these mushrooms."

I think that these four broad styles evolved together sort of to the push and the pull of society's around the world. Once again, I think what I've stumbled on is these basic styles of thinking and behaving. There's centrist certainly, the go versus the stay, stability, plasticity, male, female, libertarian I think, authoritarian, I'm using Nolan's chart, and liberal, and conservative. Indeed libertarian are taking from these estrogen, personal freedom, and from the testosterone scale economic freedom. This is it. Here is the questionnaire. I'm going to give it to you. You've got to take it on an app. When you do take it you're going to get this. I'm breaking these scales down. Nobody's just one, they're not buckets, and I have found actually a lot of men who are very empathetic but they're not contemplative, they don't ruminate.

I've found quite a few women who are very good at systems thinking testosterone, particularly women in big business, but they're not tough minded. We are all a combination. As I mentioned, I've studied 100,000 people and no two people took this questionnaire the same way. I've never in my life met two people who I thought were alike, and as I say I'm an identical twin. There's patterns to nature, there's patterns to culture, and there's patterns to personality. I'm going to leave this up while I tell a story and then go.

The story is I was in Japan and I was with and they were starting Match Japan. I was hired to go for the week and talk to the press and explain these four personality styles. Then the last day came and my wonderful little handler, I said to my handler, "So what am I doing tonight?" She says, "Well we're going to have a little party Helen." I said, "Oh okay." She said, "What we're going to do," and we pull up to this place and it looks like the White House. Big columns and I walk into this room, this huge ballroom, twice the size of this room. Mannequins with wedding dresses on them, six foot high flower arrangements, etc., and she said, "Well Helen, what we're going to do is we've invited the first four people who have taken your questionnaire on Match Japan to come to this party tonight." I said, "Well that's okay, that's great." She said, "Well what you got to do is you got to explain the four biological styles of thinking and behaving and then we're going to have a little ice breaker." I said, "Oh okay, that's cool."

She says, "Well what we're going to do is everybody's going to take your personality questionnaire and they're going to wear a rubber band around their wrist." People who are very high on the dopamine scale are going to wear a bright yellow one, energy, fun, exploration. People who are very high on the serotonin scale are going to wear royal blue, stay. People who are very high on their testosterone scale are going to wear a red one, what I call power tie red. Then tree hugger green for people who are high on the estrogen scale. They're all in there, they're all mixing, they're all wearing one of these bands, and I get up and I explain it. Then what happens is she said, "Well what we're going to do next is we're going to roll out the bottom layer of a wedding cake, four wedding cakes, just a two foot by two foot, bottom layer of a wedding cake. Four of them, and the four broad styles of thinking and behaving are going to go to different parts of the room and decorate the wedding cake and you're going to comment on it."

I said, "Holy shit, this is the nadir of my scientific life." Anyway I hoped they would do it a little differently. This is what I saw. The first thing I did is I went over to the people who were doing the estrogen cake. That cake was smiling at me. Let's be friends, love they write on the side. It's very emotional, charming, I don't think you want it on your wedding cake, but it's emotional, charming, let's connect, empathetic wedding cake. Then I go to the high testosterone cake. There's no emotion in that cake, none, but they decorated around the cake. They thought outside the box. Then I went to the high serotonin cake. It's a formal, orderly wedding cake. One kiwi, one cherry, one kiwi, one cherry, one kiwi, one cherry, organized wedding cake. Kind of person you want.

Then I go to what I'll call the libertarian cake, the dopamine cake. The first thing I see, the crow parts, there's 500 people in the room and first thing I see is three men pitching fruit at the cake. Then they look up to me and one guy was standing there, he looked at me, he took one look at me, he took some flowers out of a vase that was not part of the wedding decorations and plunged it into the middle of the cake. Here we have the libertarian cake.

I will conclude with this. As I said, I don't agree with the golden rule treat others as you would want to be treated. I believe in the platinum rule, understand who they are, talk to them so that they can hear you, and you will win. Thank you.