# Ep5 "How is your brain like a team of rivals?"

An episode of [Inner Cosmos with David Eagleman](https://invisiblenetwork.ai/podcast/1677842672), 24 Apr 2023, 41 min.

Audio: https://podtrac.com/pts/redirect.mp3/traffic.omny.fm/d/clips/e73c998e-6e60-432f-8610-ae210140c5b1/534dc725-2971-42a1-b1bf-afaa0107416e/1626bdd9-e0c1-44f6-be17-afee0053bc98/audio.mp3?utm_source=Podcast&in_playlist=bee00526-7528-4581-b6b6-afaa01083a3d

Would you kill one person to save the lives of five others? Why do you find yourself on the horns of a dilemma when someone offers you a chocolate cake? How can you believe different things at once? Find out what's running under the hood in this first episode of a three-parter about our decision making -- and how a little knowledge of neuroscience can allow us to make better decisions.

## Transcript

[0:05] Speaker 1: How is your brain like Abraham Lincoln's political cabinet? And
[0:10] Speaker 1: why is it easier to do a drone strike on
[0:12] Speaker 1: an enemy than to stab them with a bayonet? And
[0:15] Speaker 1: what does any of this have to do with Mel
[0:18] Speaker 1: Gibson or the Twilight Zone or mister Spock from Star Trek.
[0:24] Speaker 1: Welcome to Inner Cosmos with me David Eagleman. I'm a
[0:29] Speaker 1: neuroscientist and an author at Stanford University, and in these
[0:33] Speaker 1: next three episodes, we're going to sail deeply into our
[0:37] Speaker 1: three pound universe to understand why and how our lives
[0:41] Speaker 1: look the way they do. So today we're going to
[0:51] Speaker 1: discover that you're not one thing with a single drive,
[0:55] Speaker 1: but instead your brain is a team of rivals. It's
[0:59] Speaker 1: a machine that's built of conflicting parts. This is going
[1:03] Speaker 1: to allow us to understand how we make decisions, which
[1:06] Speaker 1: is what we'll focus on in this episode, and in
[1:08] Speaker 1: the next episode we'll talk about economic decisions in particular,
[1:13] Speaker 1: like how do you choose which ice cream to buy
[1:15] Speaker 1: or which car to buy? And finally, we'll talk about
[1:18] Speaker 1: how we can leverage this sort of knowledge to optimally
[1:23] Speaker 1: navigate our behavior, to make our behavior consistent with our
[1:27] Speaker 1: long term thinking rather than the temptations that sit right
[1:31] Speaker 1: in front of us. So for now, let's begin with
[1:35] Speaker 1: human behavior and why we are all so complicated. So
[1:39] Speaker 1: I'm going to start today with a story that I
[1:42] Speaker 1: told in my book Incognito, and the story is about
[1:45] Speaker 1: that two thousand and six arrest of the actor Mel Gibson.
[1:49] Speaker 1: So he was pulled over for speeding. He was going
[1:52] Speaker 1: almost twice the posted speed limit on the Pacific Coast
[1:55] Speaker 1: Highway in Malibu, and the police officer, James Me, gave
[1:59] Speaker 1: him a breath liizer test, and what that showed is
[2:02] Speaker 1: that Gibson's blood alcohol level was at zero point one
[2:05] Speaker 1: two percent, which is very high, well over the legal
[2:09] Speaker 1: limit of point eight. And there was also an open
[2:12] Speaker 1: bottle of tequila on the seat next to Gibson. So
[2:15] Speaker 1: the officer places Gibson under arrest and asks him to
[2:19] Speaker 1: get into the squad car, and Gibson goes nuts, and
[2:23] Speaker 1: he says Jews are responsible for all the wars in
[2:27] Speaker 1: the world, and he asks the officer are you a
[2:30] Speaker 1: Jew And the officer, James Me, was indeed Jewish. So
[2:35] Speaker 1: Gibson refuses to get in the squad car and he
[2:37] Speaker 1: has to be handcuffed. So within a day the website
[2:41] Speaker 1: TMZ leaks a video of this interaction, and there's this
[2:45] Speaker 1: vigorous response from the media and everything gets very heated.
[2:49] Speaker 1: So eventually Gibson writes a note of apology, and it
[2:54] Speaker 1: reads quote, after drinking alcohol on Thursday night, I did
[2:57] Speaker 1: a number of things that were very wrong and for
[3:00] Speaker 1: which I am ashamed. I acted like a person completely
[3:03] Speaker 1: out of control when I was arrested and said things
[3:06] Speaker 1: that I do not believe to be true and which
[3:08] Speaker 1: are despicable. So he goes on to say he's ashamed
[3:11] Speaker 1: and he disgraced himself, and that he's been battling alcoholism,
[3:15] Speaker 1: and he apologizes for his quote unbecoming behavior. But this
[3:21] Speaker 1: didn't really land that well because there was no reference
[3:24] Speaker 1: at all to the anti Semitic slurs. So Gibson then
[3:28] Speaker 1: writes a longer note of apology directed toward the Jewish community,
[3:31] Speaker 1: and he says, quote, there is no excuse, nor should
[3:35] Speaker 1: there be any tolerance for anyone who thinks or expresses
[3:39] Speaker 1: any kind of antisemitic remark. I want to apologize, specifically
[3:43] Speaker 1: to everyone in the Jewish community for the vitriolic and
[3:46] Speaker 1: harmful words that I said to a law enforcement officer
[3:50] Speaker 1: the night I was arrested on a dui charge. Every
[3:53] Speaker 1: human being is God's child, and if I wish to
[3:56] Speaker 1: honor my God, I have to honor his children. But please,
[4:00] Speaker 1: I know from my heart that I am not an
[4:01] Speaker 1: anti Semite. I'm not a bigot. Hatred of any kind
[4:05] Speaker 1: goes against my faith. So Gibson offered to meet one
[4:09] Speaker 1: on one with leaders of the Jewish community to quote
[4:13] Speaker 1: discern the appropriate path for healing. So he seemed genuinely apologetic,
[4:18] Speaker 1: and Jewish leaders accepted his apology. But here's the question.
[4:23] Speaker 1: Are Mel Gibson's true colors that of an anti Semite
[4:28] Speaker 1: or are his true colors those he showed afterwards in
[4:32] Speaker 1: his eloquent and apparently heartfelt apologies. Well this was a
[4:37] Speaker 1: question that got a lot of people arguing. So one
[4:40] Speaker 1: journalist wrote in the Washington Post an article that he
[4:43] Speaker 1: titled Mel Gibson it wasn't just the tequila talking, and
[4:48] Speaker 1: he wrote, quote, well, I'm sorry about his relapse, but
[4:51] Speaker 1: I just don't buy the idea that a little tequila,
[4:55] Speaker 1: or even a lot of tequila, can somehow turn an
[4:58] Speaker 1: unbiased person into a raging anti semite, or a racist,
[5:03] Speaker 1: or a homophobe, or a bigot of any kind for
[5:05] Speaker 1: that matter. Alcohol removes inhibitions, allowing all kinds of opinions
[5:10] Speaker 1: to escape uncensored. But you can't blame alcohol for forming
[5:15] Speaker 1: and nurturing those opinions in the first place. Then, the
[5:18] Speaker 1: producer of the TV show Scarborough County drank alcohol on
[5:23] Speaker 1: the show until he raised his blood alcohol level two
[5:26] Speaker 1: point one two percent, which was Gibson's level on that night,
[5:30] Speaker 1: and he reported quote, not feeling antisemitic after drinking. So,
[5:35] Speaker 1: like a lot of people, the reporter and the producer
[5:39] Speaker 1: suspected that the alcohol had loosened Gibson's inhibitions and revealed
[5:44] Speaker 1: his true self, and the nature of their suspicion has
[5:47] Speaker 1: a long history. An ancient Greek poet had coined a
[5:52] Speaker 1: popular phrase which translates to in wine, there is the truth,
[5:58] Speaker 1: and this was repeated by the Roman as in Vino veritas.
[6:03] Speaker 1: A passage in the Babylonian Talmud makes the same point
[6:06] Speaker 1: quote in came wine out went a secret. The Roman
[6:11] Speaker 1: historian Tacitus claimed that the Germanic people always drank alcohol
[6:17] Speaker 1: while holding councils to prevent anyone from lying. Okay, But
[6:22] Speaker 1: going back to Mel Gibson, not everyone agreed with the
[6:26] Speaker 1: hypothesis that alcohol revealed who he really was. A writer
[6:31] Speaker 1: in The National Review argued, quote, the guy was drunk.
[6:35] Speaker 1: For Heaven's sake. We all say and do dumb things
[6:38] Speaker 1: when we're drunk. If I were to be judged on
[6:40] Speaker 1: my drunken escapades and follies, I should be utterly excluded
[6:44] Speaker 1: from polite society. And so would you, unless you're some
[6:48] Speaker 1: kind of saint. The Jewish conservative activist David Horowitz commented
[6:53] Speaker 1: on Fox News, quote, people deserve compassion when they're in
[6:57] Speaker 1: this kind of trouble. I think it would be very
[6:59] Speaker 1: ungracious for people to deny it to him. There is
[7:02] Speaker 1: an addiction psychologist named Alan Marlott who wrote in USA
[7:06] Speaker 1: Today alcohol is not a truth serum. It may or
[7:10] Speaker 1: may not indicate his true feelings, and Gibson's social circle
[7:15] Speaker 1: publicly vouched for him. Earlier in the day before the arrest,
[7:19] Speaker 1: Gibson had spent time at the house of his friend
[7:22] Speaker 1: Dean Devlin, who was quoted saying, if Mel is an
[7:26] Speaker 1: anti Semite, he spends a lot of time with us,
[7:29] Speaker 1: which makes no sense. Devlin and his wife are both Jewish.
[7:34] Speaker 1: For Devlin, that was proof enough against the arguments of
[7:37] Speaker 1: anti Semitism. So which are Gibson's true colors? Those in
[7:43] Speaker 1: which he shouts anti Semitic comments or those in which
[7:47] Speaker 1: he feels remorse and shame and publicly says I am
[7:50] Speaker 1: reaching out to the Jewish community for its help. Now,
[7:53] Speaker 1: many people prefer a view of human nature that includes
[7:57] Speaker 1: a true side and a false side. Words, we think
[8:01] Speaker 1: that people have a genuine aim and the rest is
[8:05] Speaker 1: decoration or evasion or cover up. Now that's intuitive, but
[8:09] Speaker 1: it's incomplete. A study of the brain necessitates a more
[8:13] Speaker 1: nuanced view of human nature. And as we're going to
[8:17] Speaker 1: see in this episode, we are made of many drives
[8:20] Speaker 1: under the hood, many different networks of neurons that sometimes
[8:24] Speaker 1: have their own opinions. As the poet Walt Whitman put it,
[8:29] Speaker 1: I am large, I contain multitudes. So Gibson's detractors are
[8:35] Speaker 1: going to continue to insist that he is truly an
[8:37] Speaker 1: anti Semite, and his defenders will continue to insist that
[8:41] Speaker 1: he is not. But both may be defending an incomplete story.
[8:46] Speaker 1: So let's begin in the nineteen sixties, when the pioneers
[8:50] Speaker 1: of artificial intelligence, we're struggling to build simple robotic programs
[8:55] Speaker 1: that could manipulate small blocks of wood. So the idea
[8:59] Speaker 1: was to identify the blocks and then to grip them,
[9:04] Speaker 1: and then to stack them up in simple patterns. And
[9:07] Speaker 1: this was one of those apparently simple problems that turns
[9:10] Speaker 1: out to be incredibly hard, because for a robot, finding
[9:15] Speaker 1: a block of wood requires figuring out which camera pixels
[9:20] Speaker 1: correspond to the block and which ones don't, and then
[9:23] Speaker 1: you have to recognize the block shape regardless of the
[9:27] Speaker 1: angle and the distance of the block. And then you
[9:29] Speaker 1: have to grab it, which requires visual guidance of graspers
[9:33] Speaker 1: that have to squeeze in at the right moment from
[9:36] Speaker 1: the right direction with the right force, and stacking requires
[9:41] Speaker 1: an analysis of the rest of the blocks and adjusting
[9:44] Speaker 1: to those details. And all these programs need to be
[9:48] Speaker 1: coordinated so they happen at the right times in the
[9:51] Speaker 1: right sequence. And so what these AI pioneers discovered is
[9:56] Speaker 1: that tasks that seem simple are often masking enormous computational complexity.
[10:05] Speaker 1: So some decades ago, the computer scientist Marvin Minsky and
[10:09] Speaker 1: his colleagues started thinking about this problem and they came
[10:13] Speaker 1: up with a really progressive idea. Maybe the robot could
[10:17] Speaker 1: solve the problem by distributing the labor among specialized subagents.
[10:24] Speaker 1: So imagine small computer programs that could each bite off
[10:29] Speaker 1: a small piece of the problem. So one computer program
[10:32] Speaker 1: is in charge of the job find, another could solve
[10:36] Speaker 1: the Fetch problem. Another takes care of the stack block.
[10:40] Speaker 1: And these subagents can be connected in a hierarchy just
[10:44] Speaker 1: like a company, and they can report to one another
[10:47] Speaker 1: and to their bosses. And because of this hierarchy, stack
[10:51] Speaker 1: block would not try to start its job until Find
[10:56] Speaker 1: and Fetch had finished their jobs. So they is that
[11:00] Speaker 1: these subagents are totally mindless. But when these sub agents
[11:05] Speaker 1: come together, the whole system starts to look pretty smart.
[11:09] Speaker 1: So this idea of subagents didn't solve the problem entirely,
[11:14] Speaker 1: but it helped a lot, and most importantly, it brought
[11:17] Speaker 1: into focus a new idea about the working of biological brains.
[11:23] Speaker 1: Marvin Minsky suggested that human minds perhaps were collections of
[11:29] Speaker 1: enormous numbers of machine like mindless subagents that collaborate. So
[11:35] Speaker 1: the key idea is that a bunch of small specialized
[11:39] Speaker 1: workers can give rise to something like a society with
[11:43] Speaker 1: all kinds of rich properties that no subagent has by itself.
[11:48] Speaker 1: Each little guy is just doing some simple thing, but together,
[11:52] Speaker 1: when they're connected in the right way, you get something
[11:55] Speaker 1: that looks like intelligence. So the suggestion was that and
[12:00] Speaker 1: thousands of little minds are better than one large one.
[12:04] Speaker 1: And if this sounds weird, just think about how factories work.
[12:08] Speaker 1: Each person on the assembly line is specialized. They do
[12:11] Speaker 1: one simple job. No one there knows how to do everything,
[12:16] Speaker 1: and yet complex products get built out of this. And
[12:20] Speaker 1: this is also how government ministries operate. Each bureaucrat has
[12:25] Speaker 1: one task or a few very specific tasks, and the
[12:28] Speaker 1: government succeeds on its ability to distribute the work appropriately
[12:33] Speaker 1: and on larger scales. This is how civilizations operate. They
[12:37] Speaker 1: reach the next level of sophistication when they learn to
[12:41] Speaker 1: divide labor. They commit some people to specialize in agriculture,
[12:46] Speaker 1: and some to art, and some to warfare and so on.
[12:49] Speaker 1: This division of labor allows specialization and a deeper level
[12:54] Speaker 1: of expertise, so even though no one knows how other
[12:58] Speaker 1: jobs work, as an emergent result, you get civilization. So
[13:04] Speaker 1: this idea of dividing up problems into smaller subroutines that
[13:09] Speaker 1: ignited the young field of artificial intelligence back in the
[13:12] Speaker 1: nineteen seventies. Instead of trying to develop a single all
[13:16] Speaker 1: purpose program, the scientists changed their goal. Now it was
[13:21] Speaker 1: to build a system out of smaller, local expert networks
[13:26] Speaker 1: which know how to do one single thing. And in
[13:29] Speaker 1: this framework, the larger system only has to switch which
[13:33] Speaker 1: of the experts has control at any given moment. The
[13:36] Speaker 1: learning challenge now involves not so much how to do
[13:40] Speaker 1: each little task, but instead how to distribute who's doing
[13:44] Speaker 1: what when. So, as Minsky suggested in his book The
[13:48] Speaker 1: Society of Mind, perhaps that's all the human brain has
[13:52] Speaker 1: to do as well, and he noted that if brains
[13:55] Speaker 1: really do work this way as collections of subagents, we
[14:00] Speaker 1: wouldn't have any reason to be aware of the specialized processes.
[14:04] Speaker 1: He said, quote thousands and perhaps millions of little processes
[14:09] Speaker 1: must be involved in how we anticipate, imagine, plan, predicts,
[14:15] Speaker 1: and prevent, and yet all this proceeds so automatically that
[14:19] Speaker 1: we regard it as ordinary common sense. At first, it
[14:23] Speaker 1: may seem incredible that our minds could use such intricate
[14:27] Speaker 1: machinery and yet be unaware of it. When scientists began
[14:31] Speaker 1: to look into the brains of animals, Minsky's society of
[14:36] Speaker 1: mind idea open up a new way of looking at things.
[14:40] Speaker 1: In the early nineteen seventies, researchers realized that a frog
[14:45] Speaker 1: has at least two separate ways of seeing motion. One
[14:49] Speaker 1: system is looking for small darting objects like a fly,
[14:52] Speaker 1: and it directs the tongue, and the other system is
[14:55] Speaker 1: looking for large looming objects like a person, and it
[14:59] Speaker 1: tells the lef legs to jump. And presumably neither of
[15:02] Speaker 1: these systems is conscious. Instead, they're just simple automated programs
[15:08] Speaker 1: that are burned down in the circuitry. So the society
[15:12] Speaker 1: of mind framework was an important step forward. But despite
[15:16] Speaker 1: the initial excitement about it, a collection of experts with
[15:20] Speaker 1: divided labor has never proven sufficient to yield the properties
[15:26] Speaker 1: of the human brain. It's still the case that our
[15:28] Speaker 1: smartest robots are less intelligent than a three year old child.
[15:33] Speaker 1: So what went wrong? I suggested in my book Incognito
[15:37] Speaker 1: that a critical factor was missing from the division of
[15:41] Speaker 1: labor models, and we turn to that now. The missing
[15:45] Speaker 1: factor in Minski's theory was competition among the experts who
[15:50] Speaker 1: all believe they know the right way to solve the problem.
[15:53] Speaker 1: Just like a good drama, the human brain runs on conflict.
[15:59] Speaker 1: In an assembly line a government ministry, each worker is
[16:03] Speaker 1: an expert in a small task. But in contrast, parties
[16:07] Speaker 1: in a democracy hold different opinions about the same issues,
[16:12] Speaker 1: and the important part of the process is the battle
[16:16] Speaker 1: for steering the ship of state. Brains are like democracies.
[16:22] Speaker 1: They're built of multiple overlapping experts who weigh in and
[16:27] Speaker 1: compete over different choices. As the poet while Whitman correctly surmised,
[16:33] Speaker 1: we are large, and we harbor multitudes within us, and
[16:37] Speaker 1: those multitudes are locked in chronic battle. There's an ongoing
[16:42] Speaker 1: conversation among the different factions in your brain. They compete
[16:47] Speaker 1: to control the single output channel of your behavior. So
[16:51] Speaker 1: as a result, you can accomplish the strange feats of
[16:55] Speaker 1: arguing with yourself, or cussing yourself, or cajoling yourself. These
[17:01] Speaker 1: are things that computers simply don't do. So when the
[17:04] Speaker 1: hostess at a party offers you chocolate cake, you can
[17:08] Speaker 1: find yourself on the horns of a dilemma. Some parts
[17:11] Speaker 1: of your brain have evolved to crave the rich energy
[17:14] Speaker 1: source of sugar. Other parts of your brain care about
[17:18] Speaker 1: the negative consequences, like the health of your heart or
[17:21] Speaker 1: the bulge of your love handles. Part of you wants
[17:24] Speaker 1: the cake, and part of you tries to gather the
[17:27] Speaker 1: strength to pass on it. And the final vote of
[17:30] Speaker 1: the parliament determines which party controls what you ultimately do.
[17:36] Speaker 1: In other words, whether you put your hand up or
[17:37] Speaker 1: you put your hand out. In the end, you either
[17:41] Speaker 1: eat the chocolate cake or you don't, but you can't
[17:44] Speaker 1: do both. Because of these internal multitudes, biological creatures can
[17:50] Speaker 1: be conflicted. Now, the term conflicted can't be sensibly applied
[17:56] Speaker 1: to an entity that has a single program. Your car
[17:59] Speaker 1: can't conflicted about which way to turn. It has one
[18:02] Speaker 1: steering wheel commanded by one driver, and it follows directions
[18:06] Speaker 1: without complaint. But brains can be of two minds, and
[18:11] Speaker 1: often many more than that. We don't know whether to
[18:14] Speaker 1: turn toward the cake or away from it, because there
[18:17] Speaker 1: are several little sets of hands on the steering wheel
[18:21] Speaker 1: of our behavior. Consider this simple experiment that's been done
[18:25] Speaker 1: with laboratory rats. If you put some cheese at the
[18:28] Speaker 1: end of a little corridor, the rat will go towards
[18:31] Speaker 1: the cheese, and you can hook up a little harness
[18:34] Speaker 1: to feel how strongly he's pulling towards that. Now, let's
[18:38] Speaker 1: say instead of the cheese, you put an electrical shock.
[18:40] Speaker 1: Now the rat moves away from the electrical shock, and
[18:44] Speaker 1: with the harness you can measure the force. Okay, Now
[18:48] Speaker 1: you put both cheese and the electrical shock at the
[18:52] Speaker 1: end of the hallway. And what the rat does is
[18:54] Speaker 1: he begins to approach, but with draws, and he finds
[19:00] Speaker 1: the courage to approach again. And what happens is he
[19:02] Speaker 1: oscillates conflicted, and it's exactly at the distance where the
[19:07] Speaker 1: two forces cancel out. In other words, he's going towards
[19:11] Speaker 1: a thing, and he's pulling away from the thing, and
[19:14] Speaker 1: both programs are running at once. The pull matches the push.
[19:19] Speaker 1: The poor rat has two pairs of paws on its
[19:22] Speaker 1: steering wheel, each pulling in opposite directions, and as a result,
[19:27] Speaker 1: he can't get anywhere. So brains, whether rat or human,
[19:32] Speaker 1: are machines made of conflicting parts. If building a contraption
[19:37] Speaker 1: with internal division seems strange, just consider that we already
[19:41] Speaker 1: build social machines like this. Think of a jury of
[19:46] Speaker 1: peers in a courtroom trial. You have twelve strangers with
[19:50] Speaker 1: different opinions, and they're tasked with this single mission of
[19:54] Speaker 1: coming to a consensus. So the jurors argue and cox
[19:59] Speaker 1: and the influence, and eventually the group coheres to a
[20:03] Speaker 1: single decision, having differing opinions. It's not a drawback to
[20:08] Speaker 1: the jury system. It is the central feature. When the
[20:12] Speaker 1: President Abraham Lincoln was putting together his presidential cabinet, he
[20:16] Speaker 1: chose to put in adversaries. The historian Doris Kern's Goodwin
[20:22] Speaker 1: described his cabinet as a team of rivals, and we
[20:26] Speaker 1: see this kind of team of rivals all the time.
[20:29] Speaker 1: In Zimbabwe some years ago, the president Robert Mugabe agreed
[20:33] Speaker 1: to share power with a rival that he had earlier
[20:37] Speaker 1: tried to assassinate. And in China in two thousand and nine,
[20:40] Speaker 1: the President Hu Jintao named two opposing faction leaders to
[20:45] Speaker 1: help him craft China's future. I proposed in incognito that
[20:51] Speaker 1: the brain is best understood as a team of rivals,
[20:56] Speaker 1: and the rest of this episode and the next two
[20:58] Speaker 1: are going to explore that framework. Who the parties are,
[21:02] Speaker 1: how they compete, how the union is held together, what
[21:06] Speaker 1: happens when things fall apart. How this framework allows us
[21:10] Speaker 1: to understand what products we buy and how we can
[21:14] Speaker 1: use this understanding of the team of rivals to better
[21:18] Speaker 1: navigate our own behavior into the future. As we move along,
[21:23] Speaker 1: remember that different political parties typically have the same goal,
[21:28] Speaker 1: which is success for their country, but they just have
[21:31] Speaker 1: different ways of going about it. So, as Lincoln put it,
[21:36] Speaker 1: rivals should be turned into allies quote for the sake
[21:40] Speaker 1: of the greater good and for networks. In your brain
[21:44] Speaker 1: neural subpopulations, the common interest is the thriving and survival
[21:50] Speaker 1: of you the organism. In the same way that liberals
[21:54] Speaker 1: and conservatives both love their country but can have different
[21:58] Speaker 1: strategies for steering it. It's the same way in the
[22:01] Speaker 1: brain you have competing factions that all believe they know
[22:05] Speaker 1: the right way to solve problems. When trying to understand
[22:25] Speaker 1: the strange details of human behavior, psychologists or economists sometimes
[22:31] Speaker 1: refer to a dual process account, and you'll know this,
[22:36] Speaker 1: for example, if you've read Daniel Kahneman's book Thinking Fast
[22:40] Speaker 1: and Slow. In that framework, the brain has two separate systems.
[22:44] Speaker 1: One is fast and automatic and below the surface of
[22:48] Speaker 1: conscious awareness, and the other system is slow and cognitive
[22:53] Speaker 1: and conscious, and these two systems are always battling it out. Now,
[22:59] Speaker 1: this is a very good start to thinking about it,
[23:01] Speaker 1: but there's no real reason to assume that there are
[23:04] Speaker 1: only two systems. In fact, as we're going to see,
[23:07] Speaker 1: there are many systems, and there are also different ways
[23:11] Speaker 1: to think about how to divide things up. So in
[23:15] Speaker 1: nineteen twenty, Sigmund Freud suggested three competing parts in his
[23:20] Speaker 1: model of the psyche. There was the id, the ego,
[23:23] Speaker 1: and the superego. The id was all about instinct, the
[23:28] Speaker 1: ego was realistic and organized, and the super ego was
[23:33] Speaker 1: critical and moralizing. In the nineteen fifties, the neuroscientist Paul
[23:38] Speaker 1: MacLean suggested that the brain is made of three layers
[23:42] Speaker 1: that represent successive stages of evolutionary development. There's the reptilian brain,
[23:50] Speaker 1: which is involved in survival behaviors, and the limbic system,
[23:55] Speaker 1: which underlies the emotions. And in higher animals, there's the
[23:59] Speaker 1: neo core text, which is used in higher order thinking. Now,
[24:04] Speaker 1: the details of both Freud's model and Maclean's model have
[24:08] Speaker 1: largely fallen out of favor, but the heart of the
[24:11] Speaker 1: idea survives, which is that brains are made of competing subsystems.
[24:18] Speaker 1: I'll start with a simple model of competition as a
[24:21] Speaker 1: starting point because it captures one way to see this picture,
[24:25] Speaker 1: but by the next episode we'll see that it's even
[24:28] Speaker 1: more sophisticated than that. So we'll start with a general
[24:32] Speaker 1: statement about the brain's anatomy, which is that some areas
[24:35] Speaker 1: of your brain are involved in higher order operations regarding
[24:40] Speaker 1: events in the outside world. For the cognitionandy, this area
[24:44] Speaker 1: is like the dorsilateral prefrontal core text, which is on
[24:47] Speaker 1: the surface of your brain, just inside your temples, so
[24:50] Speaker 1: those are monitoring and assessing the outside world, while other
[24:55] Speaker 1: areas are involved with monitoring your internal state, like your
[24:59] Speaker 1: level of hunger, or your sense of motivation, or whether
[25:03] Speaker 1: something is rewarding to you. And this includes areas like
[25:06] Speaker 1: the region just behind your forehead called the medial prefrontal cortex,
[25:10] Speaker 1: in several areas deep below the surface, so these monitor
[25:14] Speaker 1: what's going on on the inside. Now, again, the real
[25:18] Speaker 1: situation is even more complex than this rough division would imply,
[25:23] Speaker 1: because brains do a lot more than just monitor the
[25:26] Speaker 1: outside and the inside. Your brain also simulates future states
[25:31] Speaker 1: and reminisces about the past and figures out where to
[25:35] Speaker 1: find things not immediately present, and so on. We'll get
[25:38] Speaker 1: into that, but for the moment, this division into systems
[25:42] Speaker 1: that monitor the outside and the inside will serve as
[25:47] Speaker 1: a rough guide, and we can refine this picture later.
[25:50] Speaker 1: Now to pick two labels that'll be familiar to everyone.
[25:54] Speaker 1: We can call these the rational and the emotional systems.
[26:00] Speaker 1: Are a little underspecified and imperfect, but they carry this
[26:04] Speaker 1: starting point about rivalries in the brain. The rational system
[26:09] Speaker 1: is the one that cares about analysis of things in
[26:12] Speaker 1: the outside world, while the emotional system monitors the internal
[26:17] Speaker 1: state and worries whether things will be good or bad.
[26:21] Speaker 1: In other words, as a rough guide, rational cognition involves
[26:25] Speaker 1: external events, while emotion involves your internal state. So you
[26:31] Speaker 1: can do a math problem without consulting your internal state,
[26:35] Speaker 1: but you have to consult your internal state to order
[26:38] Speaker 1: a dessert off the menu, or to prioritize what you
[26:41] Speaker 1: feel like doing next. The emotional networks are absolutely required
[26:47] Speaker 1: to rank your possible next actions in the world. If
[26:51] Speaker 1: you were an emotionless robot who rolled into a room,
[26:56] Speaker 1: you might be able to analyze this stuff around you,
[26:59] Speaker 1: but you would be frozen with indecision about what to
[27:03] Speaker 1: do next. Choices about the priority of actions are determined
[27:08] Speaker 1: by our internal states. When you get home, will you
[27:12] Speaker 1: head straight to your refrigerator or the bathroom or the bedroom.
[27:16] Speaker 1: That doesn't depend on the external stimuli in your home
[27:19] Speaker 1: because those haven't changed, but instead on your body's internal states.
[27:25] Speaker 1: So the battle between the rational and the emotional systems
[27:29] Speaker 1: can be brought to light by what philosophers call the
[27:32] Speaker 1: trolley dilemma. Here's the scenario. A trolley is barreling down
[27:38] Speaker 1: the train tracks. It's going out of control, and five
[27:42] Speaker 1: workers are making repairs way down the track, and you,
[27:46] Speaker 1: a bystander, realize that they're all going to get killed
[27:50] Speaker 1: by this trolley. But you also notice that there's a
[27:53] Speaker 1: lever nearby that you can throw, and that will divert
[27:57] Speaker 1: the trolley down a different track where there's a single
[28:01] Speaker 1: worker who will be killed. So what do you do?
[28:04] Speaker 1: Do you throw the lever or not? If you're like
[28:07] Speaker 1: most people, you have no hesitation about throwing the lever
[28:12] Speaker 1: because it's far better than only one person gets killed
[28:15] Speaker 1: than five people. Right, Okay, so that's a good choice.
[28:18] Speaker 1: But there's a second version. Of the trolley problem that
[28:22] Speaker 1: presents an interesting twist. Imagine that the same trolley is
[28:26] Speaker 1: barreling down the tracks. The same five workers are gonna
[28:30] Speaker 1: get killed, but this time you're a bystander on a
[28:34] Speaker 1: footbridge that goes over the tracks, and you notice that
[28:38] Speaker 1: there's an obese man standing on the footbridge, and you
[28:42] Speaker 1: realize that if you push him off the bridge, his
[28:46] Speaker 1: bulk will be sufficient to stop the train and save
[28:50] Speaker 1: the five workers. Do you push the man off? If
[28:57] Speaker 1: you're like most people, you bristle at this suggestion of
[29:01] Speaker 1: murdering an innocent person. But here's the thing. What differentiates
[29:07] Speaker 1: this from your previous choice. Aren't you trading one life
[29:12] Speaker 1: for five lives? In both versions of the dilemma? Doesn't
[29:16] Speaker 1: the math work out the same way? So what is
[29:19] Speaker 1: the difference in these two cases. Philosophers propose that the
[29:24] Speaker 1: difference lies in how people are being used. In the
[29:28] Speaker 1: first scenario, you're simply reducing a bad situation, the death
[29:33] Speaker 1: of five people, to a less bad situation, the death
[29:36] Speaker 1: of one person. In the case of the man on
[29:38] Speaker 1: the bridge, he is being exploited as a means to
[29:42] Speaker 1: an end. So that's a popular explanation in the philosophy literature,
[29:47] Speaker 1: but there's also a more brain based approach to understanding
[29:52] Speaker 1: this reversal in your choice. Neuroscientists Joshua Green and Jonathan
[29:57] Speaker 1: Cohen did brain imaging while people consider these two scenarios,
[30:02] Speaker 1: and what they found was that the difference pivots on
[30:06] Speaker 1: the emotional component of actually touching someone that is interacting
[30:11] Speaker 1: with them at a close distance. So if the problem
[30:15] Speaker 1: is constructed so that the man on the footbridge can
[30:18] Speaker 1: be dropped with the flip of a switch through a trapdoor,
[30:22] Speaker 1: many people will vote to let him drop. But there's
[30:24] Speaker 1: something about interacting with the person up close that stops
[30:28] Speaker 1: most people from pushing the man to his death. Why
[30:32] Speaker 1: it's because that sort of personal interaction activates these emotional networks.
[30:38] Speaker 1: It changes the problem from an abstract, impersonal math problem
[30:44] Speaker 1: into a personal emotional decision. So when people consider the
[30:49] Speaker 1: trolley problem, here's what the brain imaging reveals. In the
[30:53] Speaker 1: footbridge scenario, where you actually have to push the guy,
[30:57] Speaker 1: the brain areas involved in motor planning and emotion become active.
[31:02] Speaker 1: But in pulling the lever scenario, the only brain errors
[31:06] Speaker 1: involved are those involved in rational thinking. People register emotionally
[31:11] Speaker 1: when they have to push someone. But if you only
[31:14] Speaker 1: have to tip a lever, your brain behaves like mister Spock,
[31:18] Speaker 1: who's the vulcan on Star Trek, who's all rationality and
[31:21] Speaker 1: no emotion, who says emotions are alien to me. The
[31:42] Speaker 1: battle between emotional and rational networks in the brain is
[31:47] Speaker 1: nicely illustrated by an old episode of The Twilight Zone,
[31:50] Speaker 1: which I saw years ago. Here's how it goes. A
[31:53] Speaker 1: stranger in an overcoat shows up at a man's door
[31:57] Speaker 1: and proposes a deal. He says, here is a box
[32:01] Speaker 1: with a single button on it. All you have to
[32:04] Speaker 1: do is press the button, and I will pay you
[32:07] Speaker 1: one thousand dollars. The man says, what happens when I
[32:11] Speaker 1: press the button? And the stranger says, when you press
[32:14] Speaker 1: the button, someone far away, someone you don't even know,
[32:19] Speaker 1: will die. So the man suffers over this moral dilemma
[32:24] Speaker 1: through the night, and the button box rests on his
[32:27] Speaker 1: kitchen table and he stares at it, and he paces
[32:30] Speaker 1: around it, and sweat is on his brow, and he's
[32:34] Speaker 1: thinking about his desperate financial situation, and finally he lunges
[32:39] Speaker 1: to the box and he punches the button and nothing happens.
[32:43] Speaker 1: It's quiet, anticlimactic. And suddenly there's a knock at the door,
[32:48] Speaker 1: and the stranger in the overcoat is there, and he
[32:51] Speaker 1: hands the man the money and he takes the box,
[32:54] Speaker 1: and the man says, wait, what happens now, And the
[32:58] Speaker 1: stranger says, now, I take the box and I give
[33:02] Speaker 1: it to the next person, someone far away, someone you
[33:06] Speaker 1: don't even know now. I loved this story because it
[33:10] Speaker 1: highlights the ease of impersonally pressing a button. If the
[33:15] Speaker 1: man had been asked to attack someone with his hands,
[33:19] Speaker 1: he presumably would have declined the offer. In earlier times
[33:24] Speaker 1: in our evolution, there wasn't really any way to interact
[33:27] Speaker 1: with other people at any distance other than hands and
[33:31] Speaker 1: feet are possibly a stick, and that distance of interaction
[33:36] Speaker 1: was salient and consequential. And this is what our emotional
[33:41] Speaker 1: reaction reflects. But interestingly, as we evolved, the situation began
[33:46] Speaker 1: to change. Generals and even soldiers could very commonly find
[33:51] Speaker 1: themselves very far removed from the people that they were killing.
[33:55] Speaker 1: There's a great line in Shakespeare's Henry the Sixth where
[33:59] Speaker 1: a man challenges a nobleman and mocks the fact that
[34:03] Speaker 1: the nobleman has never known the danger of the battlefield.
[34:06] Speaker 1: The man says, when struckest thou one blow in the field,
[34:11] Speaker 1: and the nobleman responds, great men have reaching hands oft?
[34:17] Speaker 1: Have I struck those that I never saw? And struck
[34:20] Speaker 1: them dead? And this is what happens all the time.
[34:23] Speaker 1: In modern warfare, we can launch Tomahawk surface to surface
[34:28] Speaker 1: missiles from the deck of Navy ships with the touch
[34:31] Speaker 1: of a button. The result of pushing that button is
[34:34] Speaker 1: then watched by the missile operator live on CNN. Minutes
[34:39] Speaker 1: later when buildings in the enemy's city disappear in plumes,
[34:45] Speaker 1: so the proximity is lost, and so is the emotional influence.
[34:51] Speaker 1: This impersonal nature of waging war makes it disconcertingly easy.
[34:58] Speaker 1: I recently heard an argument between an old time fighter
[35:02] Speaker 1: pilot who was lamenting how easy it is for drone
[35:06] Speaker 1: pilots to do something, and he's right, But it should
[35:10] Speaker 1: also be noted that it's easy when you're thousands of
[35:13] Speaker 1: feet in the air. If you watch the footage of
[35:15] Speaker 1: the bombing of Hiroshima and Nagasaki, which was dropping these
[35:20] Speaker 1: ten thousand pound nuclear bombs onto civilian targets, you'll hear
[35:25] Speaker 1: the total casualness of the pilot even though each bomb
[35:29] Speaker 1: wiped out almost one hundred thousand people, and in fact,
[35:33] Speaker 1: the pilot later said quote, I made up my mind
[35:36] Speaker 1: then that the morality of dropping that bomb was not
[35:39] Speaker 1: my business. I was instructed to perform a military mission
[35:42] Speaker 1: to drop the bomb. Now, I'm not making a judgment
[35:45] Speaker 1: about a military pilot's obligation in the middle of a
[35:48] Speaker 1: world war. It was a complex issue that is difficult
[35:52] Speaker 1: to be understood by a modern audience who hasn't just
[35:55] Speaker 1: lived through years of war and is looking for a
[35:58] Speaker 1: way to end it. That I am saying saying it's
[36:01] Speaker 1: surprising to see how easy it appeared to press the
[36:05] Speaker 1: button to open the bomb doors from thirty three thousand
[36:09] Speaker 1: feet in the air, as opposed to if the pilot
[36:11] Speaker 1: had been sent in to murder one hundred thousand civilians,
[36:15] Speaker 1: including women and children, with a knife or with his hands.
[36:19] Speaker 1: I assume it would have been a very different experience
[36:22] Speaker 1: for him. So, in thinking about these issues about how
[36:26] Speaker 1: easy it is to wage war when it's impersonal, one
[36:30] Speaker 1: political thinker in the nineteen sixties suggested that the button
[36:35] Speaker 1: to launch a nuclear war should be implanted in the
[36:39] Speaker 1: chest of the president's closest friend. That way, if the
[36:44] Speaker 1: president wants to make the decision to annihilate millions of
[36:47] Speaker 1: people on the other side of the globe, he'd first
[36:49] Speaker 1: have to physically harm his friend. He'd have to rip
[36:53] Speaker 1: open his chest to get at the button that would
[36:57] Speaker 1: at least engage his emotional system in the decision making
[37:02] Speaker 1: so as to guard against letting the choice be impersonal.
[37:07] Speaker 1: Because both of these neural systems battle to control the
[37:11] Speaker 1: single output channel of your behavior, emotions can tip the
[37:15] Speaker 1: balance of decision making, and this ancient battle has turned
[37:19] Speaker 1: into a directive of sorts from many people. If it
[37:23] Speaker 1: feels bad, it is probably wrong. Now, there are lots
[37:27] Speaker 1: of counter examples to this. For example, you can find
[37:31] Speaker 1: yourself put off by a particular choice, but still conclude
[37:35] Speaker 1: that it's not morally wrong, like putting your pet down
[37:39] Speaker 1: when it gets too old and sick, even though it
[37:42] Speaker 1: breaks your heart. Nonetheless, emotion serves as a generally useful
[37:48] Speaker 1: steering mechanism for decision making. The emotional systems are evolutionarily
[37:54] Speaker 1: quite old, and they're shared with many other species, while
[37:57] Speaker 1: the development of the rational system is more recent. But
[38:02] Speaker 1: the novelty of the rational system doesn't necessarily indicate that
[38:06] Speaker 1: it's by itself superior. Societies would not be better off
[38:11] Speaker 1: if everyone were like the vulcan mister Spock, all rationality
[38:15] Speaker 1: and no emotion. Instead, a balance, a teaming up of
[38:20] Speaker 1: the internal rivals is probably optimal for brains. And that's
[38:25] Speaker 1: because the disgust that we feel at pushing the man
[38:29] Speaker 1: off the footbridge is critical to social interaction. The impassivity
[38:34] Speaker 1: that one feels at pressing a button to launch a
[38:36] Speaker 1: Tomahawk missile is probably detrimental to civilization. Some balance of
[38:43] Speaker 1: the emotional and rational systems is needed, and that balance
[38:46] Speaker 1: may already be optimized by natural selection in human brains. Or,
[38:51] Speaker 1: to put it in another way, a democracy that is split
[38:54] Speaker 1: across the aisle maybe just what you want, because a
[38:58] Speaker 1: takeover in either direction would almost certainly prove less optimal.
[39:03] Speaker 1: The ancient Greeks had an interesting analogy for life that
[39:07] Speaker 1: captured this wisdom. The idea was that life is as
[39:10] Speaker 1: though you are a charioteer and your chariot is being
[39:14] Speaker 1: pulled by two horses. One is the horse of reason
[39:18] Speaker 1: and the other is the horse of passion. One horse
[39:21] Speaker 1: is always trying to tug you off one side of
[39:23] Speaker 1: the road, and the other is trying to pull you
[39:25] Speaker 1: off the other side, and your job is to hold
[39:28] Speaker 1: on to them tightly and keep them in check so
[39:32] Speaker 1: that you can continue down the middle of the road.
[39:37] Speaker 1: And that's what we try to do with the brain
[39:39] Speaker 1: networks involved in rationality and emotion. So what we've introduced
[39:44] Speaker 1: in today's episode is the way in which the brain
[39:47] Speaker 1: is a machine built out of conflicting parts. In the
[39:51] Speaker 1: next episode, we're going to explore how this team of
[39:54] Speaker 1: rivals expresses itself in very particular ways, like how we
[39:59] Speaker 1: choose what to buy or how much something should cost.
[40:02] Speaker 1: This is the basis of a new type of economics
[40:05] Speaker 1: called neuroeconomics, so tune into that to uncover the next
[40:10] Speaker 1: juicy bits. That's all for this week. To find out
[40:17] Speaker 1: more and to share your thoughts, head over to eagleman
[40:20] Speaker 1: dot com, slash Podcasts, and you can also watch full
[40:24] Speaker 1: episodes of Inner Cosmos on YouTube. Subscribe to my channel
[40:28] Speaker 1: so you can follow along each week for new updates
[40:31] Speaker 1: until next time. This is Inner Cosmos and I'm David Eagleman.

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