Ad hominem, from the Latin "against man", is the fallacy of attacking those who present an argument rather than responding to the argument itself. It's one of the most common maneuvers in any argument, because it works, even without proving anything.
How the fallacy works
The attack changes its target: instead of examining whether the statement is true, the person who made it is attacked. "You can't talk about the economy, you never had money." The phrase looks like an answer, but it doesn't answer anything about economics, it just disqualifies whoever said it.
The logical error is simple to name: the origin of an idea does not decide whether it is true. A truth spoken by the mouth of an adversary remains true, and a lie spoken by a saint remains a lie. Judging content by its source means exchanging the right question for one that is easier to win.
Why does he fool even smart people?
The ad hominem convinces because it diverts attention from the difficult part of the discussion, the merit of the argument, to the easy part, a real or invented flaw on the part of the speaker. And since there is almost always something criticizable in any person, the attack seems to have substance, even without touching on what was at stake.
How to recognize and respond
The question that disarms the ad hominem is always the same: "does what you said about me change anything about what I said?" If the answer is no, the fallacy is exposed. It's worth remembering that pointing out a real character flaw has its place, it just doesn't decide whether a specific argument is right or wrong, these are separate issues.
Ad hominem is one of several common fallacies; see also the strawman fallacy and the difference between truth and validity, which explains why judging by content, not origin, is what supports a good argument.
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What does ad hominem mean?
It is a Latin expression that means "against man". Names the fallacy of attacking those who present an argument, instead of responding to the argument itself.
Why is ad hominem a fallacy?
Because the origin of an idea, or the character of whoever defends it, does not decide whether it is true or false. A truth told by someone questionable remains true.
What is an example of an ad hominem?
"You can't talk about the economy, you never had money." The phrase attacks the person and completely ignores whether what they said about economics is right or wrong.
The other cluster fallacies: What is the strawman fallacy · What is false dilemma · What is appeal to the majority
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