Freud's 1920 monograph Beyond the Pleasure Principle marks a turning point in his idea of the most basic forces governing mental life. In it he asserts the existence of a genuine exception to the pleasure principle that he regards as sufficiently far-reaching to require a restructuring of the theory.

The exception consists of people's compulsive repetition of previous experiences in the absence of any evident payoff: when people return repeatedly to horrific moments of their lives, as soldiers with post-traumatic stress disorder might do in recurrently dreaming a catastrophic shelling in the trenches, they bring on an experience with no redeeming value, according to Freud. Called the repetition compulsion, the tendency toward these repetitions can override the pleasure principle.

Freud extrapolates from the repetition compulsion to the existence of a death instinct, a trend toward quiescence and dissolution present in all living things: life first arose from inorganic material, and individual living entities return to that state at death. Death and inorganicity also represent the complete absence of stimulation; individuals verge on returning to that state on a smaller scale insofar as they strive toward the reduction of stimulation, the aim expressed by the pleasure principle and what Freud will present as its refinements.

Finally, introducing a new dualism as the overarching dynamic of mental life, Freud conceives the death instinct as operating in opposition to the life instincts, which by the end of the monograph subsume both the sexual and ego instincts of his former schematic. The sexual and ego instincts, although thus grouped together, retain the potential for conflict Freud previously observed them to have (see Chapter 5).

This work is, by Freud's own admission, one of his most speculative and far-fetched, especially the portion in which he derives and then justifies the death instinct and posits some of its consequences; the narrative is one of his most obscure. But psychological insight and intriguing turns of argument abound in its pages, which repay patient attention.