The purpose of violence is to force respect from other people. The less self-respect people feel, the more they are dependent on respect from others; for without a certain minimal amount of respect, from others or the self, the self begins to feel dead inside, numb and empty. That is how the most violent criminals told me they felt, and it is clear that it is the most intolerable of all feelings (though it is actually an absence of feeling, lack of the feeling of pride, or self-love). When people lack self-respect, and feel they are incapable of eliciting respect from others in the form of admiration for their achievements or their personalities, they may see no way to get respect except in the form of fear, which I think of as a kind of ersatz substitute for admiration; and violence does elicit fear, as it is intended to. For example, I have spoken to many violent criminals who spoke of how gratifying it was to see fear in the eyes of their victims.

James Gilligan (b. c. 1936) American psychiatrist and author

Preventing Violence, ch. 1 (2001)
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