have grappled with this question for centuries:

what makes people go wrong?

Interestingly, I asked this question when I was a little kid.

When I was a kid growing up in the South Bronx, inner-city ghetto

in New York, I was surrounded by evil,

as all kids are who grew up in an inner city.

And I had friends who were really good kids,

who lived out the Dr. Jekyll Mr. Hyde scenario -- Robert Louis Stevenson.

That is, they took drugs, got in trouble, went to jail.

Some got killed, and some did it without drug assistance.

So when I read Robert Louis Stevenson, that wasn't fiction.

The only question is, what was in the juice?

And more importantly, that line between good and evil --

which privileged people like to think is fixed and impermeable,

with them on the good side, and the others on the bad side --

I knew that line was movable, and it was permeable.

Good people could be seduced across that line,

and under good and some rare circumstances, bad kids could recover

with help, with reform, with rehabilitation.

So I want to begin with this this wonderful illusion

by [Dutch] artist M.C. Escher.

If you look at it and focus on the white,

what you see is a world full of angels.

But let's look more deeply, and as we do,

what appears is the demons, the devils in the world.

And that tells us several things.

One, the world is, was, will always be filled with good and evil,

because good and evil is the yin and yang of the human condition.

It tells me something else. If you remember,

God's favorite angel was Lucifer.

Apparently, Lucifer means "the light."

It also means "the morning star," in some scripture.

And apparently, he disobeyed God,

and that's the ultimate disobedience to authority.

And when he did, Michael, the archangel, was sent

to kick him out of heaven along with the other fallen angels.

And so Lucifer descends into hell, becomes Satan,

becomes the devil, and the force of evil in the universe begins.

Paradoxically, it was God who created hell as a place to store evil.

He didn't do a good job of keeping it there though.

So, this arc of the cosmic transformation

of God's favorite angel into the Devil,

for me, sets the context for understanding human beings

who are transformed from good, ordinary people

into perpetrators of evil.

So the Lucifer effect, although it focuses on the negatives --

the negatives that people can become,

not the negatives that people are --

leads me to a psychological definition. Evil is the exercise of power.

And that's the key: it's about power.

To intentionally harm people psychologically,

to hurt people physically, to destroy people mortally, or ideas,

and to commit crimes against humanity.

If you Google "evil," a word that should surely have withered by now,

you come up with 136 million hits in a third of a second.

A few years ago -- I am sure all of you were shocked, as I was,

with the revelation of American soldiers

abusing prisoners in a strange place

in a controversial war, Abu Ghraib in Iraq.

And these were men and women

who were putting prisoners through unbelievable humiliation.

I was shocked, but I wasn't surprised,

because I had seen those same visual parallels

when I was the prison superintendent of the Stanford Prison Study.

Immediately the Bush administration military said ... what?

What all administrations say when there's a scandal.

"Don't blame us. It's not the system. It's the few bad apples,

the few rogue soldiers."

My hypothesis is, American soldiers are good, usually.

Maybe it was the barrel that was bad.

But how am I going to -- how am I going to deal with that hypothesis?

I became an expert witness

for one of the guards, Sergeant Chip Frederick,

and in that position, I had access to the dozen investigative reports.

I had access to him. I could study him,

have him come to my home, get to know him,

do psychological analysis to see, was he a good apple or bad apple.

And thirdly, I had access to all of the 1,000 pictures

that these soldiers took.

These pictures are of a violent or sexual nature.

All of them come from the cameras of American soldiers.

Because everybody has a digital camera or cell phone camera,

they took pictures of everything. More than 1,000.

And what I've done is I organized them into various categories.

But these are by United States military police, army reservists.

They are not soldiers prepared for this mission at all.

And it all happened in a single place, Tier 1-A, on the night shift.

Why? Tier 1-A was the center for military intelligence.

It was the interrogation hold. The CIA was there.

Interrogators from Titan Corporation, all there,

and they're getting no information about the insurgency.

So they're going to put pressure on these soldiers,

military police, to cross the line,

give them permission to break the will of the enemy,

to prepare them for interrogation, to soften them up,

to take the gloves off. Those are the euphemisms,

and this is how it was interpreted.

Let's go down to that dungeon.

(Camera shutter)

(Thuds)

(Camera shutter)

(Thuds)

(Breathing)

(Bells)

So, pretty horrific.

That's one of the visual illustrations of evil.

And it should not have escaped you that

the reason I paired the prisoner with his arms out

with Leonardo da Vinci's ode to humanity

is that that prisoner was mentally ill.

That prisoner covered himself with shit every day,

and they used to have to roll him in dirt so he wouldn't stink.

But the guards ended up calling him "Shit Boy."

What was he doing in that prison

rather than in some mental institution?

In any event, here's former Secretary of Defense Rumsfeld.

He comes down and says, "I want to know, who is responsible?

Who are the bad apples?" Well, that's a bad question.

You have to reframe it and ask, "What is responsible?"

Because "what" could be the who of people,

but it could also be the what of the situation,

and obviously that's wrongheaded.

So how do psychologists go about understanding

such transformations of human character,

if you believe that they were good soldiers

before they went down to that dungeon?

There are three ways. The main way is -- it's called dispositional.

We look at what's inside of the person, the bad apples.

This is the foundation of all of social science,

the foundation of religion, the foundation of war.

Social psychologists like me come along and say, "Yeah,

people are the actors on the stage,

but you'll have to be aware of what that situation is.

Who are the cast of characters? What's the costume?

Is there a stage director?"

And so we're interested in, what are the external factors

around the individual -- the bad barrel?

And social scientists stop there, and they miss the big point

that I discovered when I became an expert witness for Abu Ghraib.

The power is in the system.

The system creates the situation that corrupts the individuals,

and the system is the legal, political, economic, cultural background.

And this is where the power is of the bad-barrel makers.

So if you want to change a person, you've got to change the situation.

If you want to change the situation,

you've got to know where the power is, in the system.

So the Lucifer effect involves understanding

human character transformations with these three factors.

And it's a dynamic interplay.

What do the people bring into the situation?

What does the situation bring out of them?

And what is the system that creates and maintains that situation?

So my book, "The Lucifer Effect," recently published, is about,

how do you understand how good people turn evil?

And it has a lot of detail

about what I'm going to talk about today.

So Dr. Z's "Lucifer Effect," although it focuses on evil,

really is a celebration of the human mind's

infinite capacity to make any of us kind or cruel,

caring or indifferent, creative or destructive,

and it makes some of us villains.

And the good news story that I'm going to hopefully come to

at the end is that it makes some of us heroes.

This is a wonderful cartoon in the New Yorker,

which really summarizes my whole talk:

"I'm neither a good cop nor a bad cop, Jerome.

Like yourself, I'm a complex amalgam

of positive and negative personality traits

that emerge or not, depending on the circumstances."

(Laughter)

There's a study some of you think you know about,

but very few people have ever read the story. You watched the movie.

This is Stanley Milgram, little Jewish kid from the Bronx,

and he asked the question, "Could the Holocaust happen here, now?"

People say, "No, that's Nazi Germany,

that's Hitler, you know, that's 1939."

He said, "Yeah, but suppose Hitler asked you,

'Would you electrocute a stranger?' 'No way, not me, I'm a good person.' "

He said, "Why don't we put you in a situation

and give you a chance to see what you would do?"

And so what he did was he tested 1,000 ordinary people.

500 New Haven, Connecticut, 500 Bridgeport.

And the ad said, "Psychologists want to understand memory.

We want to improve people's memory,

because memory is the key to success." OK?

"We're going to give you five bucks -- four dollars for your time."

And it said, "We don't want college students.

We want men between 20 and 50."

In the later studies, they ran women.

Ordinary people: barbers, clerks, white-collar people.

So, you go down, and one of you is going to be a learner,

and one of you is going to be a teacher.

The learner's a genial, middle-aged guy.

He gets tied up to the shock apparatus in another room.

The learner could be middle-aged, could be as young as 20.

And one of you is told by the authority, the guy in the lab coat,

"Your job as teacher is to give this guy material to learn.

Gets it right, reward him.

Gets it wrong, you press a button on the shock box.

The first button is 15 volts. He doesn't even feel it."

That's the key. All evil starts with 15 volts.

And then the next step is another 15 volts.

The problem is, at the end of the line, it's 450 volts.

And as you go along, the guy is screaming,

"I've got a heart condition! I'm out of here!"

You're a good person. You complain.

"Sir, who's going to be responsible if something happens to him?"

The experimenter says, "Don't worry, I will be responsible.

Continue, teacher."

And the question is, who would go all the way to 450 volts?

You should notice here, when it gets up to 375,

it says, "Danger. Severe Shock."

When it gets up to here, there's "XXX" -- the pornography of power.

(Laughter)

So Milgram asks 40 psychiatrists,

"What percent of American citizens would go to the end?"

They said only one percent. Because that's sadistic behavior,

and we know, psychiatry knows, only one percent of Americans are sadistic.

OK. Here's the data. They could not be more wrong.

Two thirds go all the way to 450 volts. This was just one study.

Milgram did more than 16 studies. And look at this.

In study 16, where you see somebody like you go all the way,

90 percent go all the way. In study five, if you see people rebel, 90 percent rebel.

What about women? Study 13 -- no different than men.

So Milgram is quantifying evil as the willingness of people

to blindly obey authority, to go all the way to 450 volts.

And it's like a dial on human nature.

A dial in a sense that you can make almost everybody totally obedient,

down to the majority, down to none.

So what are the external parallels? For all research is artificial.

What's the validity in the real world?

912 American citizens committed suicide or were murdered

by family and friends in Guyana jungle in 1978,

because they were blindly obedient to this guy, their pastor --

not their priest -- their pastor, Reverend Jim Jones.

He persuaded them to commit mass suicide.

And so, he's the modern Lucifer effect,

a man of God who becomes the Angel of Death.

Milgram's study is all about individual authority to control people.

Most of the time, we are in institutions,

so the Stanford Prison Study is a study