Argumentum ad hysteria

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
An argumentum ad hysteria argument has the basic form:

Examples

 * "Your argument for the legitimacy of your gender identity is invalid because you have a mental disorder that is gender dysphoria."
 * "Your argument about discrimination against the disabled is invalid because you're a diagnosed How can we be certain you're not just being paranoid?"
 * Drapetomania — or the idea that there's something medically wrong with black people not wanting to be human livestock.
 * "There’s nothing wrong with the Soviet Union, comrade! You only think that because you’re suffering from "
 * "Why should I accept anything said from an insane homosexual?" from when homosexuality was considered a mental disorder
 * "The government isn’t spying on us. You’re just paranoid!"
 * Dismissing women's complaints as female hysteria
 * "These 30 'crazy' people have been proven RIGHT by history."