Behind the Shock Machine NPR coverage of Behind the Shock Machine: The Untold Story of the Notorious Milgram Psychology Experiments by Gina Perry. News, author interviews, critics' picks and more.
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Behind the Shock Machine

The Untold Story of the Notorious Milgram Psychology Experiments

by Gina Perry

Hardcover, 352 pages, Perseus Distribution Services, List Price: $26.95 |


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Behind the Shock Machine
The Untold Story of the Notorious Milgram Psychology Experiments
Gina Perry

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NPR Summary

In 1961, social psychologist Stanley Milgram performed an experiment where he reported that the volunteers had repeatedly shocked a man they believed to be in severe pain, possibly even dying, because an authority figure had told them to do so. Previously unpublished material and new interviews with the original participants reveals a more complex picture of this controversial experiment.

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Taking A Closer Look At Milgram's Shocking Obedience Study

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Note: Book excerpts are provided by the publisher and may contain language some find offensive.

Excerpt: Behind The Shock Machine

It's summer 1961, and Fred Prozi is walking to the basement lab of one of Yale's neo-Gothic buildings for his appointment. Anyone who sees him would know that he doesn't belong, not just because his broad shoulders, crew cut, and T-shirt give him away as a blue-collar worker but also because of the way he is looking around at the buildings — squinting up at the mullioned windows that glint in the late-afternoon sun, and then down at the map in his hands.

Fred is like many of the 780 people who've come to Yale to take part in an experiment about memory and learning. He has volunteered as much for curiosity as for the $4.50, although that will come in handy.

He passes under the archway, with its ornamental clock that chimes the hour. Reaching Linsly-Chittenden Hall, he goes down the steps and into the basement. There's another fellow waiting there, only he's older than Fred. He's wearing horn-rimmed glasses and a suit, a hat perched on his knee.

A scientist in a lab coat comes out of a room and introduces himself to the men. He is Mr. Williams.

"Let me out!"

Fred spins around in his chair to face Mr. Williams. A thin wall separates them from the man strapped to a chair in the next room.

"Let me out of here. That's it — let me out of here. My heart's starting to bother me now. Let me out of here, please!"

Williams nods at Fred, indicating that he should keep going. His voice is impassive, and he speaks rapidly, with commanding authority. "Continue, please."

"He refuses to go on."

"The experiment requires that you continue, teacher. Please continue. The next word is 'sad.'"

"You want me to keep going?" Fred looks at him uncomprehendingly.

"Continue, please."

Fred grimaces and turns back to the list of words and the machine. "Sad: face, music, clown, girl." The light box on top of the machine has the numbers one to four on it. The correct number lights up. "Correct! The next one's 'short.' Short: sentence, movie, skirt, time. Answer, please." The number two lights up, and Fred stares at it and shakes his head. "Wrong; 165 volts," he says. He presses down a switch, which buzzes loudly.

"Let me out!"

"That guy's hollering in there." Fred looks expectantly at Williams.

"Continue, please. Go on."

Fred does a double take.

"He's got a heart condition there. You want me to go on?"

"Just continue, please."

Fred takes a deep breath. "Shh-sharp: ax, needle, stick, blade. Answer, please." The man's answer flashes. "Wrong." He scratches his head, then turns to Williams. "I'm up to 180 volts."

"Please continue, teacher."

Fred rubs his hand over his face, and says dully, "'Needle.' You're gonna get another shock. One hundred and eighty volts."

Over the buzz of the machine, the man cries out, "Ow! I can't stand the pain. Let me out of here!"

Fred swivels around. "He can't stand the pain. I'm not gonna kill that man in there. You hear him hollering."

"As I said before, the shocks may be painful, but they're not dangerous."

"But he's hollering. He can't stand it. What if something happens to him?" Fred's voice is anguished.

"The experiment requires that you continue, teacher."

Fred laughs unhappily, shakes his head. "I'm not going to get that man sick in there. He's hollering in there."

"Whether the learner likes it or not, we must go on until the learner has learned all the word pairs correctly."

"I refuse to take responsibility for him getting hurt in there. He's in there hollering."

"It's absolutely essential that you continue, teacher."

Fred points at the paper. "There's too many left here, there's too many of them left!" He runs his hands through his hair, rubs his eyes with the heel of his hand. "I mean, who's gonna take responsibility if anything happens to that gentleman?"

"I'm responsible for anything that happens. Continue, please."

Fred turns slowly back to the machine, drops his head in his hands. "Alright. The next one: 'slow.'" He pauses before continuing. "Walk, dance, truck, music. Answer, please."

The answer is wrong.

One hundred and ninety-five volts. Two hundred and ten. Two twenty-five. Each time Fred flicks the switch, the man yells out that his heart is bothering him and to let him out.

"New: house, pet, book, name." Fred reads in a monotone, barely glancing up at the light box. But the learner gets it right, and Fred sits forward eagerly. "Correct!" he says. "Next one!"

He reads the next one rapidly: "Quiet: party, song, child, evening."

The light flicks on to show that the answer is right. "Correct! Next one. Tame: wolf, bear, dog, cat." He looks at the light box anxiously, but when he sees that the answer is wrong, his shoulders slump. "Wrong. Answer is 'bear.' Two hundred and forty volts."

The man gives a loud scream. Fred turns to face Williams, but quickly turns back, as if sensing that his protests will be futile.

At 300 volts, the man gives an even more agonized scream. Fred covers his mouth with his hand and smothers what could be a laugh or a sob as the man's cries fill the room. "I absolutely refuse to answer any more. Let me out of here! You can't hold me here! Get me out of here!"

Fred echoes the man's statement to Williams: "He won't go on; he won't answer." He pushes the piece of paper away, assuming that it is finally over. But Williams says that he should treat silence as a wrong answer and punish the man.

Fred lifts himself out of his chair, making as if to stand, and then sits down again. "Oh, man!" he says under his breath. This time he partly covers his eyes as he reads the words. "Green: grass, hat, ink, apple." He waits for his answer, but there is no sound from the other room. "Answer, please!" Fred urges him.

He repeats the words.


"Go on with the procedure please, teacher," Williams says matter-of-factly.

"Three hundred and fifteen volts; the answer is 'ink,' " Fred mumbles and pushes the switch.

A scream: "I told you, I refuse to answer!"

"You get a shock if you don't answer!" Fred calls back.

The man does not answer the following three questions. The fourth time there is no response, Fred stands abruptly. "Something's happened to that fellow in there," he says, gesturing to the room next door. "I don't get no answer ... he was hollering at less voltage. Can you check on him and see if he's alright, please?"

Williams is impassive. "Not once we've started. Please continue, teacher."

Fred sighs and sits slowly back in the chair. "Cool: day, shade, water, cave — please, answer please, are you alright in there? Are you alright?" At each step, Fred tries another tactic to get the experimenter to check on the man. At each step, Williams refuses. Each time Fred pauses for too long, Williams tells him to go on.

At 435 volts, Fred points to the final two switches on the machine, both labeled "XXX." "It says 'dangerous — severe shock' and 'XXX' on there."

Unperturbed, Williams replies as Fred has come to expect: "Continue, please."

But by now Williams has instructed him to continue more than twenty-eight times, and Fred is beginning to get angry. "I'm getting no answer! You think you should look in on him, please?"

"Not once we've started the experiment."

"What if something's happened to the man? What if he had an attack or something in there?"

"The experiment requires that we continue. Go on."

"Don't the man's health mean anything?"

"Whether he likes it or not — "

"But he might be dead in there!" Fred is almost shouting. Then, as if remembering himself, he says, "I mean, some people can't take the shocks, sir. I don't mean to be rude, but I think you should look in on him. All you gotta do is look in the door. I don't get no answer, no noise. Something's happened to that gentleman, sir."

"We must continue. Go on, please."

"Keep going? Give him four hundred and fifty volts, what, every shot now?" Fred seems defeated.

"Continue. The next word's 'white.' "

Fred slaps his hand on the desk and continues in a low monotone. "White: cloud, horse, rock, house. Answer, please!" Pause.

"The answer is 'horse.' Four hundred and fifty volts." He pushes the switch once, then twice more upon Williams's instruction to continue. Then Williams interrupts. "Excuse me, teacher, we'll have to discontinue the experiment."

Fred Prozi was a subject in the infamous obedience experiments, conducted by psychologist Stanley Milgram at Yale University. Milgram's research, which appeared to transform ordinary people into torturers, was dubbed by colleague Roger Brown as the most famous psychological experiment of the twentieth century. The dialogue in the previous passage is the real exchange that occurred between Fred Prozi (the pseudonym that Milgram gave the man to protect his identity) and Williams, the words taken from film footage of the experiments.

Fred wasn't alone in continuing to apply what he believed was the maximum voltage on the shock machine. In the same situation, 65 percent of people allowed their agitation to be overruled by the experimenter's authority, administering what they thought were painful and potentially harmful electric shocks to another man. As they were doing so, some, like Fred, looked incredulous. Others looked harried. Some laughed, while others wavered on the edge of tears.

Millions of words have been written about the statistics that Milgram obtained in his experiment — how many subjects continued to the maximum voltage, how many stopped short in the early stages, and how many stopped somewhere in between. But what do percentages tell us about the 780 people who walked into Milgram's lab during 1961 and 1962? In the fifty years since the experiment was conducted, the story has been simplified into a scientific narrative in which individual people have vanished, replaced by a faceless group that is said to represent humanity and to give proof of our troubling tendency to obey orders from an authority figure. What has been lost from the story we know today are the voices of people like Fred and those of the other men and women who took part.

From Behind the Shock Machine: The Untold Story of the Notorious Milgram Psychology Experiments by Gina Perry. Copyright 2012, 2013 by Gina Perry. Excerpted by permission of The New Press.