‘The masters’ have been disposed of; the morality of the common man has won. One may conceive of this victory as at the same time a blood-poisoning
Nietzsche identifies the triumph of slave morality — the morality of ‘the herd’ — as a world-historical event initiated through Jewish and Christian revaluation, figured metaphorically as a civilizational ‘blood-poisoning.’
, On the Genealogy of Morals, 1887thesis