What say you, Messrs. Dion, Ignatieff, Rae et al.? Do you agree with this stunt? Not surprisingly, the Nazis do. (Anti-semitic link deleted). ……

(From the good folks at Wikipedia):

The genetic fallacy is a fallacy of irrelevance where a conclusion is suggested based solely on something or someone’s origin rather than its current meaning or context. This overlooks any difference to be found in the present situation, typically transferring the positive or negative esteem from the earlier context.

The fallacy therefore fails to assess the claim on its merit. The first criterion of a good argument is that the premises must have bearing on the truth or falsity of the claim in question.^[1] Genetic accounts of an issue may be true, and they may help illuminate the reasons why the issue has assumed its present form, but they are irrelevant to its merits. ^[2]

According to the Oxford Companion to Philosophy, the term originates in Morris Cohen and Ernest Nagel’s book Logic and Scientific Method.

Illustrative Example for those who may have failed their logic course:

From Attacking Faulty Reasoning by T. Edward Damer, Third Edition p. 36:

“You’re not going to wear a wedding ring, are you? Don’t you know that the wedding ring originally symbolized ankle chains worn by women to prevent them from running away from their husbands? I would not have thought you would be a party to such a sexist practice.” There may be reasons why people may not wish to wear wedding rings, but it would be logically inappropriate for a couple to reject the notion of exchanging wedding rings on the sole grounds of its alleged sexist origins.