Logical Fallacy
A logical fallacy is a false argument by design. This is as opposed to a false argument by reason, which is simply a falsehood. If you have been linked to this page, it is most likely because you make a lot of these.
Common Fallacies
Petitio principii - a circular argument
Argumentum ad hominem - an argument in which the person is attacked instead of the theory
Argumentum ad populum - the belief that something is correct because it is popular
Appeal to motive- where a premise is dismissed by calling into question the motives of its proposer. A subset of this is the George Scott Fallacy, in which it is stated that an arguer does not truly believe their argument.
Straw man- where an argument which distorts the opponent's argument. For example, in a debate between a creationist and an evolutionist a straw man would be the creationist arguing against atheism instead of evolution.
Ignoratio elenchi- similar to a straw man, where an argument is presented which does not refute the opponent's argument. For example, in a court of law this fallacy would be the defense lawyer arguing not that what his/her client did was legal, but rather that it *should* be legal.