Stanley Milgram, answered from the texts and cited to the page.
Binding factors are the forces that hold a person in place once he has entered a situation of obedience — the psychological underbrush, as I once put it, that stands between a subject's position at the shock generator and a genuine act of defiance.1 The simplest way to see them is to ask what a person would actually have to do to break off.
It is not merely a matter of deciding to stop. Many subjects in my experiments reached the intellectual conclusion that they should go no further — one man told the experimenter directly, "He can't stand it. I'm not going to kill that man in there" — and yet continued pressing the switches.2 The verbal decision and the bodily act came apart. That gap is where binding factors live.
Several forces produce it. There is politeness, the desire to honour a commitment already made, the sheer awkwardness of withdrawal.3 These are not trivial; a measure of ordinary social courtesy turns out to be among the forces that inhibit disobedience, which is a disturbing thing to notice about human sociability. Then there is the sequential structure of the action itself: each shock delivered makes the previous ones harder to repudiate.4
To stop is to say that everything done up to that point was wrong; to continue is to be reassured about it. The subject is implicated into the destructive behaviour incrementally, step by step, until the accumulated weight of prior acts becomes itself a binding force. And alongside these, a narrowing of attention: subjects become absorbed in the technical procedure — reading word pairs with care, pressing switches precisely — and lose sight of the broader moral consequences of what they are doing.5
The goal-setting, the moral assessment, is entrusted to the authority being served. None of this is rational deliberation failing. It is something more structural than that: the situation itself is organised so that exit becomes progressively harder to accomplish even when the person has already, in some interior sense, decided to leave.
The best way to begin tracing these forces is to ask: What does the subject have to go through if he wants to break off? Through what psychological underbrush must he cut to get from his position in front of the shock generator to a stance of defiance?Obedience to Authority, An Experimental View
One subject tells the experimenter: 'He can't stand it. I'm not going to kill that man in there. You hear him hollering in there. He's hollering. He can't stand it.' Although at the verbal level the subject has resolved not to go on, he continues to act in accord with the experimenter's commands.Obedience to Authority, An Experimental View
They include such factors as politeness on his part, his desire to uphold his initial promise of aid to the experimenter, and the awkwardness of withdrawal.Obedience to Authority, An Experimental View
As the subject delivers more and more painful shocks, he must seek to justify to himself what he has done; one form of justification is to go to the end... Earlier actions give rise to discomforts, which are neutralized by later ones. And the subject is implicated into the destructive behavior in piecemeal fashion.Obedience to Authority, An Experimental View
One such mechanism is the tendency of the individual to become so absorbed in the narrow technical aspects of the task that he loses sight of its broader consequences... The subject entrusts the broader tasks of setting goals and assessing morality to the experimental authority he is serving.Obedience to Authority, An Experimental View