Subhuman animals suspend their predatory (and counter-predatory) instincts in intraspecies behaviour only with the aid of inhibitions. Nevertheless, they may make use of the techniques of these instincts in intraspecies acts. In man too we can find inhibitions against destructive tendencies, and yet acceptance of interspecific techniques within the strivings of the erotic instincts. I suggest that primitive interspecific tendencies constitute death instinct in man. These tendencies are normally controlled by the libidinization of their techniques, but occasionally the primary destructive tendency breaks through.

Regression facilitates break-through of death instinct. Both can be encouraged by frustration, attack, and guilt. Death instinct may express itself as narcissistic regression.