Reductio ad Hitlerum

Reductio ad Hitlerum, also known as playing the Hitler card, is a logical fallacy described by Leo Strauss, a philosopher, in 1951.^[1][2] It happens when someone compares their opponent's view with Hitler or something that he did.^[3]

It is a form of ad hominem, distracting from the argument by criticizing the opponent. It works because in the modern world, people think of Nazism as a bad thing.^[4]

During the 2016 US Presidential Election, Republican candidate Donald J. Trump has been repeatedly compared to Hitler by commentators and comedians.^[5][6]

An example is as follows:

• Person 1 suggests that X is true.
• Person 2 says that Hitler said that too, and so X is not true.

As person 2 has criticized the opponent as opposed to the argument by comparing them to Hitler without giving any reasons as to why X is not true, they have committed reductio ad Hitlerum.