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Argumentum ad hysteria

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The appeal to hysteria, or argumentum ad hysteria, is the (informal) fallacy of painting one's opponent as mentally ill in order to discredit their argument. It is a variant of the ad hominem fallacy which is a fallacy of irrelevant premise. It is fallacious because one's mental status, regardless if one is mentally ill or not, does not entail that one's argument is invalid, or one's statements/beliefs are false.

This is distinct from the clinical context of labeling a delusional belief as delusional with sufficient ethical grounds. It is an appeal to hysteria fallacy which takes it that because someone is mentally ill (whether one actually is or not) then whatever one says must therefore be false or unreasonable.

Form[edit]

An argumentum ad hysteria argument has the basic form:

P1: Person A makes claim X.
P2: Person A is claimed to be mentally ill.
P3: Whatever claims mentally ill people make are false.
C: Therefore claim X is false.

Examples[edit]

See also[edit]

References[edit]