An ad hominem fallacy was originally considered an appeal to authority and has only recently been considered as ad hominem fallacy (Ad, 2005). It consists of asserting that the claim made by someone else is wrong, and attacks the claim because of some trait of the person rather than on the facts of the matter. For example, if A makes a statement B, then C attacks A as being an unreliable person, or not knowing the subject B well enough to talk about it. C does not concern themselves with whether or not B is correct, but rather on the reliability of A to be saying it.
Assaults on someone's character do not per se constitute an ad hominem fallacy, but do so only if they are said to try and convince others that what the person is saying or claiming is unreliable because of defects in the person's character, not in the argument he is resenting (Siris, 2004). The ad hominem argument was first identified by Aristotle in his On Sophistical Refutations (Ad, 2005). It took the form that if a person makes a claim and there is something objectionable about the person, then the claim must be false. Ad hominem fallacies come in
several subtypes: Ad hominem abusive; Ad hominem circumstantial; and Ad hominem tu quoque. The abusive form often involves just insulting a person, but can also involve pointing out serious character flaws, and it is fallacious in that the damaging facts do nothing to undermine the person's arguments or statements, but merely attack his character. The ad hominem circumstantial uses the person's circumstances to undermine their argument, even though they may have nothing to do with what they are saying, so these too, are false. Ad hominem tu quoque is a hypocritical argument because it occurs when two statements made by a person are contradictory, or the statement can also be applied to the person who is making the accusation.
Ad hominem. 92005). Retrieved July 6, 2005 from:
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