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Ethics — History — Audiobooks

The Origin and Development of the Moral Ideas
by Edward Westermarck

Between Heathenism and Christianity
by Charles William Super, Plutarch, Lucius Annaeus Seneca

Moral Science; a Compendium of Ethics
by Alexander Bain

Four Phases of Morals: Socrates, Aristotle, Christianity, Utilitarianism
by John Stuart Blackie