Reducio ad hitlerum

Reductio ad Hitlerum (pseudo-Latin for "reduction to Hitler"; sometimes argumentum ad Hitlerum, "argument to Hitler", ad Nazium, "to Nazism"), or playing the Nazi card, is an attempt to invalidate someone else's position on the basis that the same view was held by Adolf Hitler or the Nazi Party, for example: "Hitler was against tobacco smoking, X is against tobacco smoking, therefore X is a Nazi".

Coined by Leo Strauss in 1951, reductio ad Hitlerum borrows its name from the term used in logic, reductio ad absurdum (reduction to the absurd). According to Strauss, reductio ad Hitlerum is a form of ad hominem, ad misericordiam, or a fallacy of irrelevance. The suggested rationale is one of guilt by association. It is a tactic often used to derail arguments, because such comparisons tend to distract and anger the opponent, as Hitler and Nazism have been condemned in the modern world.

Reductio ad Hitlerum is a form of association fallacy. The argument is that a policy leads to – or is the same as – one advocated or implemented by Adolf Hitler or the Third Reich and so "proves" that the original policy is undesirable.

Another instance of reductio ad Hitlerum is asking a question of the form "You know who else...?" with the deliberate intent of impugning a certain idea or action by implying Hitler held that idea or performed such action.

An invocation of Hitler or Nazism is not a reductio ad Hitlerum when it illuminates the argument instead of causing distraction from it.

The phrase reductio ad Hitlerum is first known to have been used in an article written by University of Chicago professor Leo Strauss for Measure: A Critical Journal in spring 1951; it was made famous in a book by the same author published in 1953Natural Right and History, Chapter II:

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