Running Notes on Moral Relativity

Westermarck came up with it first..

Anything that can ever be said about moral relativity has probably already been anticipated by Westermarck.

Two volumes of The Origin and Development of Moral Ideas have:

  1. All the anthropological and ethnographical evidence you'll ever need to argue that moral norms vary across culture. Nothing upto 1905 is left out.

  2. An early argument for Haidt's social intuitionism, stating that all “morality” stems from moral emotion rather than reason.

  3. Repudiations of common arguments against moral relativity, such as relativity being overly permissive of “dangerous” notions.

    Ethical subjectivism is commonly held to be a dangerous doctrine, destructive to morality, opening the door to all sorts of libertinism. ... This inference was long ago drawn from the teaching of the Sophists and it will no doubt be still repeated as an argument against any theorist who dares to assert that nothing can be said to be truly right or wrong.

    Far from being a danger, ethical subjectivism seems to me more likely to be an acquisition for moral practice. Could it be brought home to people that there is no absolute standard in morality, they would perhaps be somewhat more tolerant in their judgments, and more apt to listen to the voice of reason.

  4. An explanation for why a “clearly subjective” experience is treated as having objective roots by appealing to language and history.

Westermarck is mesmerizing and original, yet nobody but anthropologists seem to recall him.


Moral relativity says that if cultural variations in morality exist, then objective morality does not exist.

This seems easy. If you look for a black cat, and find no black cat exists, then you are justified in believing no black cat is actually there.

Yet everybody seems to find flaws with this:

  1. People say you can have variations in moral rules, but not moral principles – that is, all moral rules are simply expressions of natural moral desires, like not wanting to harm people, thus making moral relativism a shallow explanation.

  2. People say moral relativism is permissive of harm, making moral relativism indefensible from a “saving the world” standpoint.

  3. People say that moral relativism doesn't permit enquiry into whether some belief systems have better reasons for holding beliefs than others – moral relativism is a descriptive, not a prescriptive treatment.

You just can't seem to please people! But the latter objections have merit in a practical sense: people look to ethicists to lay out guidelines for minimizing harm, and leave the business of the “truth” of ethics to philosophers. Applied ethicists can't use moral relativism, and so it languishes in the sidelines while effective altruism and co. attract attention.