the death instinct manifested itself as destructive aggression, a force in the psyche which endeavored to destroy or dissolve all the integrated ‘unities’ that Eros strove to create.
Kalsched rehearses Freud’s dualistic instinct theory in full — Thanatos as the dissolutive counterpart to Eros — and traces its extension into primary masochism and superego sadism.
, The Inner World of Trauma: Archetypal Defences of the Personal Spirit, 1996thesis