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  • Professor Paul Bloom: On Monday we--I presented an

  • introduction to evolutionary psychology, the looking at

  • psychology from an evolutionary perspective, and trying to make

  • a case and give some examples of how it can help illuminate and

  • illustrate certain aspects of how the mind works.

  • One of the advantages of an evolutionary perspective on the

  • mind is that it forces us to look scientifically at what we

  • would otherwise take for granted.

  • There are a lot of aspects of how we are and what we are and

  • what we do that seem so natural to us.

  • They come so instinctively and easily it's difficult,

  • and sort of unnatural, to step back and explore them

  • scientifically but if we're going to be scientists and look

  • at the mind from a scientific perspective we have to get a

  • sort of distance from ourselves and ask questions that other

  • people would not normally think to ask.

  • And the clearest case of this arises with the emotions.

  • And as a starting point there's a lovely quote from the

  • psychologist and philosopher William James that I want to

  • begin with. So, he writes:

  • To the psychologist alone can such questions occur as:

  • Why do we smile when pleased and not scowl?

  • Why are we unable to talk to a crowd as we talk to a single

  • friend? Why does a particular maiden

  • turn our wits upside down? The common man--[None of you

  • are the common man.] The common man can only say,

  • "Of course we smile. Of course our heart palpitates

  • at the sight of the crowd. Of course we love the maiden.

  • And so probably does each animal feel about the particular

  • things it tends to do in the presence of certain objects.

  • To the lion it is the lioness which is made to be loved;

  • to the bear the she-bear. To the broody hen,

  • the notion would probably seem monstrous that there should be a

  • creature in the world to whom a nestful of eggs was not utterly

  • fascinating and precious and never to be too-much-sat-upon

  • object which it is to her. Now, there's a few things to

  • note about this passage. First, it's incredibly sexist.

  • It assumes not just merely in reflexive use of phrases.

  • It assumes that--William James assumes he's talking to males,

  • male humans who sometimes take the perspective of male bears.

  • And so, it assumes a male audience.

  • You wouldn't normally--You wouldn't actually ever write

  • this way. A second point is it's

  • beautifully written and you're not--;also, not allowed to write

  • that way anymore either. It's poetic and lyrical and

  • if--William James characteristically writes that

  • way. I think he writes so much

  • better than his brother, Henry James,

  • an obscure novelist. [laughter]

  • Finally though, the point that he makes is a

  • terrific one, which is yes,

  • all of these things seem natural to us but the reason why

  • they seem natural is not because they are in some sense necessary

  • or logical truths. Rather, they emerge from

  • contingent aspects of our biological nature.

  • And so we need to step back. We actually--We need to step

  • back and ask questions like--and these are questions we're going

  • to ask--Why does poop smell bad? Avoid the temptation to say,

  • "Well, poop smells bad because it's so stinky."

  • The stinkiness of poop is not an irreducible fact about the

  • universe. Rather, the stinkiness of poop

  • is a fact about human psychology.

  • To a dung beetle poop smells just fine.

  • Why does chocolate taste good? Well, chocolate--The good

  • tastiness of chocolate isn't some necessary fact about the

  • world. It's a fact about our minds

  • that doesn't hold true for many other creatures.

  • And so, we have to step back and ask why to us do we find

  • chocolate appealing? Why do we love our children?

  • Don't say they're lovable. Many of them are not [laughter]

  • and, as William James points out, every animal,

  • most animals, many animals love their

  • children. They think their children are

  • precious and wonderful. Why?

  • Why do we get angry when people hit us?

  • Suppose somebody walked up to you and slapped you in the face?

  • You'd be afraid. You'd be angry.

  • Would you get sleepy, feel nostalgic,

  • suddenly desire some cold soup? [laughter] No.

  • Those are stupid alternatives. Of course if somebody slapped

  • us you would--we would get angry or afraid.

  • Why? Why do we feel good when

  • someone does us a favor? Why don't we feel angry?

  • Why don't we feel fearful? What we're going to do

  • throughout this course is step back and ask these questions.

  • We're going to ask questions nobody would have otherwise

  • thought to ask, where the common man wouldn't

  • address, and this is,

  • of course, standard in all sciences.

  • The first step to insight is to ask questions like why do things

  • fall down and not up? And I imagine the first person

  • who articulated the question aloud probably met with the

  • response saying, "What a stupid question.

  • Of course things fall down." Well, yes, of course things

  • fall down, but why? Why is our flesh warm?

  • Why does water turn solid when it gets cold?

  • These are natural facts about the universe,

  • but the naturalness needs to be explained and not merely

  • assumed. In this class we're going to

  • explore, throughout the course, what seems natural to us and

  • try to make sense of it. And to that end we have to ask

  • questions that you wouldn't normally ask.

  • We've already done this to some extent with domains such as

  • visual perception, memory, language and

  • rationality, but now we're going to move to the case where it's

  • maybe even somewhat more difficult to do this.

  • Now, we're going to start dealing with the emotions.

  • We're going to talk about the emotions, why they exist,

  • what they're there for, and how they work.

  • I want to start off with the wrong theory of the emotions.

  • And the wrong theory of the emotions is beautifully

  • illustrated in the television and movie series Star

  • Trek. In this alternative fantasy

  • world, there are characters, Mr.

  • Spock in the original Star Trek, Data in one of the

  • spin-offs, who are described as competent,

  • capable, in fact in many ways, super competent and super

  • capable people. But they're described as not

  • having emotions. Spock is described as not

  • having emotions because he's half Vulcan, from a planet where

  • they lack emotions. Data is an android who is said

  • to lack an emotion chip. This lack of emotions on

  • this--on a TV series does not hurt them much.

  • They're able to fully function. And in fact,

  • in a TV series emotions are often seen as a detriment.

  • You do better off without them. And there are many people in

  • sort of common sense who might think "Gee, if only I could just

  • use my rationality, think reasonably and rationally

  • and not let my emotions guide my behavior I'd be much better

  • off." It turns out that this is a

  • notion of how to think about the emotions that is deeply wrong.

  • And in fact, makes no sense at all.

  • Using the example of Star Trek, Steven Pinker,

  • in his book How the Mind Works, nicely illustrates

  • the problem here. He writes, "Spock must have

  • been driven by some motives or goals.

  • Something must have led him to explore strange new worlds,

  • to seek out new civilizations and to boldly go where no man

  • had gone before." Presumably, it was intellectual

  • curiosity that set him to drive and solve problems.

  • It was solidarity with his allies that led him to be such a

  • competent and brave officer. What would he have done if

  • attacked by a predator or an invading Klingon?

  • Did he do a handstand, solve the four-color map

  • theorem? Presumably, a part of his brain

  • quickly mobilized his faculties to scope out how to flee and how

  • to take steps to avoid a vulnerable predicament in the

  • future. That is, he had fear.

  • Spock did not walk around naked around the ship.

  • Presumably, he felt modesty. He got out of bed.

  • Presumably, he had some ambitions and drive.

  • He engaged in conversations. Presumably, he had some

  • sociable interests. Without emotions to drive us we

  • would do nothing at all. And you could illustrate this

  • scientifically. Creatures like Spock and Data

  • don't exist in the real world but there are unusual and

  • unfortunate cases where people lose,

  • to some extent or another, their emotions.

  • And you could look at these people and see what happens to

  • them. The classic case,

  • the most famous case, is that of a man called Phineas

  • Gage. Phineas Gage is the classic

  • Intro Psych examplean extremely poor guy,

  • poor schmuck. In 1848--He was a construction

  • foreman. In 1848 he was working at a

  • site with explosives and iron rods.

  • And due to an explosion, an iron rod passed through his

  • head like so. Imagine that rod shooting

  • upwards. It went under his eye and

  • popped out the top of his head. It landed about one hundred

  • feet away covered with blood and brains.

  • The rod itself weighed thirteen pounds.

  • Amazingly, Gage was not killed. In fact, he was knocked

  • unconscious only for a short period and then he got up and

  • his friends surrounded him and asked, "Are you okay?"

  • And they--And then they took him to the hospital.

  • On the way to the hospital, they stopped by a tavern and he

  • had a little pint of cider to drink, sat down and talked to

  • people. And then he had an infection,

  • had to have surgery. But when it was all said and

  • done he wasn't blind, he wasn't deaf,

  • didn't lose language, didn't become aphasic,

  • no paralysis, no retardation.

  • In some sense, what happened was much worse.

  • He lost his character. Here's a description at the

  • time of what Gage was like. And this is from Damasio's

  • excellent book Descartes' Error:

  • He used to be a really responsible guy,

  • a family man, very reliable,

  • very trustworthy. But after the accident he was

  • fitful, irreverent, indulging at times in the

  • grossest profanity, manifesting but little

  • deference for his fellows, impatient of restraint or

  • advice, a child in his intellectual

  • capacities and manifestations. He had the animal pleasures of

  • a strong man. His foul language is so debased

  • that women are advised not to stay long in his presence.

  • And he couldn't hold a job. He lost his family,

  • couldn't hold a job. He ended up in the circus.

  • He was in the circus going around the country with his big

  • iron rod telling everybody the story as they surrounded him and

  • clapped. There are other cases like

  • Phineas Gage, cases where people have had

  • damage to that same part of the brain, parts of the frontal

  • cortex. And what they've lost is they

  • basically lost a good part of their emotions.

  • And what this means is they don't really care that much

  • about things. They can't prioritize.

  • Damasio tells a case of one of his patients who was under the

  • pseudonym here of Elliot. And Elliot had a tumor in his

  • frontal lobe. And the tumor had to be removed

  • and with it came a lot of Elliot's frontal lobe.

  • And again, as a result of this, Elliot was not struck blind or

  • deaf or retarded, and he didn't become the sort

  • of profane character that Phineas Gage became,

  • but he lost the ability to prioritize.

  • He lost the ability to set goals.

  • Damasio describes him here:

  • At his job at an activity he would read and fully

  • understand the significance of the material [He works in an

  • office.] but the problem was he was

  • likely, all of a sudden,

  • to turn from the task he had initiated to doing something

  • else and spending an entire day doing that.

  • He might spend an entire afternoon deliberating on which

  • principle of categorization he should apply to files.

  • Should it be the date or the size of the document,

  • pertinence to the case or another?

  • He couldn't set his goals. He couldn't--He ended up not

  • being able to keep a job, not being able to deal with

  • people. And these are not men who have

  • lost their emotions. There is no case around where

  • you could have your emotions entirely blotted out.

  • But they lost a large part of their emotional capacity and as

  • a result, their rationality failed.

  • Emotions set goals and establish priorities.

  • And without them you wouldn't do anything, you couldn't do

  • anything. Your desire to come to class to

  • study, to go out with friends, to read a book,

  • to raise a family, to be--to do anything are

  • priorities set by your emotions. Life would be impossible

  • without those emotions. And so, there's certain themes

  • we're going to explore here. The first is this,

  • that emotions are basically mechanisms that set goals and

  • priorities and we're going to talk a lot about--in this class

  • and the next class about universals.

  • We're also going to talk about culture.

  • It turns out that cultures, different cultures,