Informal Fallacies: Relevance
Fallacies of relevance — ad hominem, straw man, red herring, appeal to authority, and appeal to emotion — the tricks that derail arguments.
When the Evidence Does Not Connect
A fallacy of relevance occurs when the premises of an argument are not actually relevant to the conclusion. The argument might feel persuasive because it triggers emotional responses or exploits cognitive shortcuts, but the logical connection is missing.
Ad hominem attacks the person making the argument instead of the argument itself. 'Senator Jones's healthcare proposal is flawed because she has no medical degree.' Whether Senator Jones has a medical degree is irrelevant to whether her proposal is sound. Ad hominem is the most common fallacy in political discourse because attacking a person is easier than refuting their argument.
Straw man misrepresents an opponent's position to make it easier to attack. 'My opponent wants to reduce military spending, so clearly he wants to leave America defenseless.' The opponent probably wants a smaller reduction, not zero defense spending. The attacker has replaced the real position with an extreme caricature.