Logical Fallacies and the Art of Debate

[ZombieHorde]

Straw man. This is the fallacy of refuting a caricatured or extreme version of somebody's argument, rather than the actual argument they've made. Often this fallacy involves putting words into somebody's mouth by saying they've made arguments they haven't actually made, in which case the straw man argument is a veiled version of argumentum ad logicam. One example of a straw man argument would be to say, "Mr. Jones thinks that capitalism is good because everybody earns whatever wealth they have, but this is clearly false because many people just inherit their fortunes," when in fact Mr. Jones had not made the "earnings" argument and had instead argued, say, that capitalism gives most people an incentive to work and save. The fact that some arguments made for a policy are wrong does not imply that the policy itself is wrong.

Argumentum ad hominem (argument directed at the person). This is the error of attacking the character or motives of a person who has stated an idea, rather than the idea itself. The most obvious example of this fallacy is when one debater maligns the character of another debater (e.g, "The members of the opposition are a couple of fascists!"), but this is actually not that common. A more typical manifestation of argumentum ad hominem is attacking a source of information -- for example, responding to a quotation from Richard Nixon on the subject of free trade with China by saying, "We all know Nixon was a liar and a cheat, so why should we believe anything he says?" Argumentum ad hominem also occurs when someone's arguments are discounted merely because they stand to benefit from the policy they advocate -- such as Bill Gates arguing against antitrust, rich people arguing for lower taxes, white people arguing against affirmative action, minorities arguing for affirmative action, etc. In all of these cases, the relevant question is not who makes the argument, but whether the argument is valid.

http://www.csun.edu/~dgw61315/fallacies.html">Much more at this link.