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.
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.
George Scott Fallacy
While not a true fallacy by any dictionary definition, the George Scott Fallacy is invoked when a person accuses a speaker of not actually believing what he or she is saying. For instance, parents regularly convince their children of Santa Claus when they themselves do not believe. An outside observer would be correct in pointing out that the parent does not believe in Santa, but in doing so they would be committing the George Scott Fallacy.
When debating, using the George Scott Fallacy is generally considered a point of concession. Belief in what you're debating should not influence your ability to debate the point. So when the opposition must resort to accusing the debater of not truly believing, they are attacking the debater, not the issue.
The term, "George Scott Fallacy," came from a correspondence between George Scott and George Airy where Scott said, speaking about Samuel Robotham, "I do not for one moment believe that he believes his own theory.[Flat Earth Theory]" While it is possible that Scott could have been right, the point is irrelevant. Rowbotham did not require belief to present his arguments for a flat Earth and Scott is in error criticizing Rowbotham rather than his theory.