going back to Freud and hitting a couple of loose ends.

There was a point in my lecture on Wednesday where I skipped

over some parts. I said, "We don't have time for

this" and I just whipped past it.

And I couldn't sleep over the weekend.

I've been tormented. I shouldn't have skipped that

and I want to hit--Let me tell you why I skipped it.

The discussion I skipped was the discussion of why we would

have an unconscious at all. So, I was talking about the

scientifically respectable ideas of Freud and I want to talk

about some new ideas about why there could be an unconscious.

Now, the reason why I skipped it is I'm not sure this is the

best way to look at the question.

As we will learn throughout the course, by far the vast majority

of what our brains do, the vast majority of what our

minds do, is unconscious and we're unaware of it.

So the right question to ask may not be, "Why are some things

unconscious?" but rather, why is this tiny

subset of mental life--why is this conscious?

On the other hand, these claims about the utility

of unconsciousness, I think, are provocative and

interesting. So I just wanted to quickly

share them with you. So, the question is,

from an evolutionary standpoint, "Why would an

unconscious evolve?" And an answer that some

psychologists and biologists have given is deception.

So, most animals do some deception.

And deception defined broadly is simply to act or be in some

way that fools others into believing or thinking or

responding to something that's false.

There's physical examples of deception.

When threatened, chimpanzees--their hair stands

up on end and that makes them look bigger to fool others to

thinking they're more dangerous than they are.

There's an angler fish at the bottom of the ocean that has a

rod sticking up from the top of its head with a lure to capture

other fish – to fool them in thinking that this is something

edible and then to themselves be devoured.

But humans, primates in general but particularly humans,

are masters of deception. We use our minds and our

behaviors and our actions continually to try to trick

people into believing what's not true.

We try to trick people, for instance,

into believing that we're tougher, smarter,

sexier, more reliable, more trustworthy and so on,

than we really are. And a large part of social

psychology concerns the way in which we present ourselves to

other people so as to make the maximally positive impression

even when that impression isn't true.

At the same time, though, we've also evolved very

good lie detection mechanisms. So not only is there

evolutionary pressure for me to lie to you, for me to persuade

you for instance, that if we're going to have

a--if you are threatening me don't threaten me,

I am not the sort of man you could screw around with.

But there's evolutionary pressure for you to look and

say, "No. You are the sort of man you

could screw around with. I can tell."

So how do you become a good liar?

And here's where the unconscious comes in.

The hypothesis is: the best lies are lies we tell

ourselves. You're a better liar,

more generally, if you believe the lie that

you're telling. This could be illustrated with

a story about Alfred Hitchcock. The story goes--He hated

working with child actors but he often had to.

And the story goes--He was dealing with a child actor who

simply could not cry. And, finally frustrated,

Hitchcock went to the actor, leaned over,

whispered in his ear, "Your parents have left you and

they're never coming back." The kid burst into tears.

Hitchcock said, "Roll ‘em" and filmed the

kid. And the kid,

if you were to see him, you'd say, "That's--Boy,

he's--he really looks as if he's sad" because he was.

If I had a competition where I'd give $100,000 to the person

who looks the most as if they are in pain,

it is a very good tactic to take a pen and jam it into your

groin because you will look extremely persuasively as if you

are in pain. If I want to persuade you that

I love you, would never leave you, you can trust me with

everything, it may be a superb tactic for me to believe it.

And so, this account of the evolution of the unconscious is

that certain motivations and goals,

particularly sinister ones, are better made to be

unconscious because if a person doesn't know they have them they

will not give them away. And this is something I think

we should return to later on when we talk about social

interaction and social relationships.

One other thing on Freud--just a story of the falsification of

Freud. I was taking my younger child

home from a play date on Sunday and he asked me out of the blue,

"Why can't you marry your mother or your father?"

Now, that's actually a difficult question to ask--to

answer for a child, but I tried my best to give him

an answer. And then I said--then I thought

back on the Freud lecture and so I asked him, "If you could marry

anybody you want, who would it be?"

imagining he'd make explicit the Oedipal complex and name his

mother. Instead, he paused for a moment

and said, "I would marry a donkey and a big bag of

peanuts." [laughter]

Both his parents are psychologists and he hates these

questions and at times he just screws around with us.

[laughter] Okay. Last class I started with Freud

and now I want to turn to Skinner.

And the story of Skinner and science is somewhat different

from the story of Freud. Freud developed and championed

the theory of psychoanalysis by himself.

It is as close as you could find in science to a solitary

invention. Obviously, he drew upon all

sorts of sources and predecessors but psychoanalysis

is identified as Freud's creation.

Behaviorism is different. Behaviorism is a school of

thought that was there long before Skinner,

championed by psychologists like John Watson,

for instance. Skinner came a bit late into

this but the reason why we've heard of Skinner and why Skinner

is so well known is he packaged these notions.

He expanded upon them; he publicized them;

he developed them scientifically and presented

them both to the scientific community and to the popular

community and sociologically in the 1960s and 1970s.

In the United States, behaviorism was incredibly well

known and so was Skinner. He was the sort of person you

would see on talk shows. His books were bestsellers.

Now, at the core of behaviorism are three extremely radical and

interesting views. The first is a strong emphasis

on learning. The strong view of behaviorism

is everything you know, everything you are,

is the result of experience. There's no real human nature.

Rather, people are infinitely malleable.

There's a wonderful quote from John Watson and in this quote

John Watson is paraphrasing a famous boast by the Jesuits.

The Jesuits used to claim, "Give me a child until the age

of seven and I'll show you the man,"

that they would take a child and turn him into anything they

wanted. And Watson expanded on this

boast, Give me a dozen healthy

infants, well-formed and my own specified world to bring them up

and I'll guarantee to take any one at random and train them to

become any type of specialist I might select--doctor,

lawyer, artist, merchant, chief,

and yes, even beggar-man and thief, regardless of his

talents, penchants, tendencies,

abilities, vocations and race of his ancestors.

Now, you could imagine--You could see in this a tremendous

appeal to this view because Watson has an extremely

egalitarian view in a sense. If there's no human nature,

then there's no sense in which one group of humans by dint of

their race or their sex could be better than another group.

And Watson was explicit. None of those facts about

people will ever make any difference.

What matters to what you are is what you learn and how you're

treated. And so, Watson claimed he could

create anybody in any way simply by treating them in a certain

fashion.

A second aspect of behaviorism was anti-mentalism.

And what I mean by this is the behaviorists were obsessed with

the idea of doing science and they felt,

largely in reaction to Freud, that claims about internal

mental states like desires, wishes, goals,

emotions and so on, are unscientific.

These invisible, vague things can never form the

basis of a serious science. And so, the behaviorist

manifesto would then be to develop a science without

anything that's unobservable and instead use notions like

stimulus and response and reinforcement and punishment and

environment that refer to real world and tangible events.

Finally, behaviorists believed there were no interesting

differences across species. A behaviorist might admit that

a human can do things that a rat or pigeon couldn't but a

behaviorist might just say, "Look.

Those are just general associative powers that differ"

or they may even deny it. They might say,

"Humans and rats aren't different at all.

It's just humans tend to live in a richer environment than

rats." From that standpoint,

from that theoretical standpoint, comes a

methodological approach which is,

if they're all the same then you could study human learning

by studying nonhuman animals. And that's a lot of what they

did. Okay.

I'm going to frame my introduction--my discussion of

behaviors in terms of the three main learning principles that

they argue can explain all of human mental life,

all of human behavior. And then, I want to turn to

objections to behaviorism but these three principles are

powerful and very interesting.

The first is habituation. This is the very simplest form

of learning. And what this is is technically

described as a decline in the tendency to respond to stimuli

that are familiar due to repeated exposure.

"Hey!" "Hey!"

The sudden noise startles but as it--as you hear it a second

time it startles less. The third time is just me being

goofy. It's just--It's--You get used

to things. And this, of course,

is common enough in everyday life.

We get used to the ticking of a clock or to noise of traffic but

it's actually a very important form of learning because imagine

life without it. Imagine life where you never

got used to anything, where suddenly somebody steps

forward and waves their hand and you'd go,

"Woah," and then they wave their hand again and you'd go,

"Whoah," and you keep--[laughter]

And there's the loud ticking of a clock and you say,

"Hmmm." And that's not the way animals

or humans work. You get used to things.

And it's actually critically important to get used to things

because it's a useful adaptive mechanism to keep track on new

events and objects. It's important to notice

something when it's new because then you have to decide whether

it's going to harm you, how to deal with it,

to attend to it, but you can't keep on noticing

it. And, in fact,

you should stop noticing it after it's been in the

environment for long enough. So, this counts as learning

because it happens through experience.

It's a way to learn through experience, to change your way

of thinking through experience. And also, it's useful because

harmful stimuli are noticed but when something has shown itself

to be part of the environment you don't notice it anymore.

The existence of habituation is important for many reasons.

One thing it's important for is clever developmental

psychologists have used habituation as a way to study

people, creatures who can't talk like

nonhuman animals, and young babies.

And when I talk on Wednesday about developmental psychology

I'll show different ways in which psychologists have used