Ethical Relativity is a 1932 book by the Finnish philosopher Edvard Westermarck, one of his main works.

The book argues for both psychological relativism (the verifiable observation that norms differ between cultures) and ethical relativism, and attempts to base ethics on the biological basis for emotions.

Westermarck argues for ethical relativism by emphasizing that there is no empirical basis for objective standards in ethical theory.

[2] Ethical Relativity was a widely noted contribution to international discussion of its subject.

[3] The book was perceived as the most polemical expression of Westermarck's views, which remained little changed since he published The Origin and Development of the Moral Ideas in 1906.