the sense of ‘duty’ as we find it pervading the life of modern man from the period of the Reformation up to the present in religious or secular rationalizations, is intensely colored by hostility against the self. ‘Conscience’ is a slave driver, put into man by himself.
Fromm argues that modern duty is not authentic moral commitment but an internalized compulsion rooted in self-hostility, functioning as a psychic mechanism of domination disguised as conscience.
, Escape from Freedom, 1941thesis