“Several psychoanalytic writers have not been troubled by this distinction between animate and inanimate forms of the stability principle and have sought to equate Freud’s death instinct, through Fechner’s inanimate principle of absolute stability, with the second law of thermodynamics (e.g. Alexander, 1921; Bernfeld and Feitelberg, 1930; Lichtenstein, 1935; and Saul, 1958). The second law of thermodynamics, otherwise known as the law of entropy, specifies that all forms of energy—for instance, heat—tend to dissipate within a closed system. Entropy, the measure of unavailable energy within a system, is therefore a directional and irreversible quantity reflecting the tendency of things to ‘run themselves down’. Seen in terms of this entropy principle, Freud’s death instinct has become considerably more palatable to certain psychoanalysts by virtue of a respectable alliance with the physical sciences.”

“Psychology, too, felt the impulse of thermodynamic ideas, which lurk behind such concepts as libidinal energy, affect charge, and arguably, the death instinct. The lines of debate between those who do and those who do not find the second law behind Freud’s death instinct are admirably drawn by Frank Sulloway (Freud: Biologist of the Mind, 1979).”