Logical Fallacies (OT)

When making an argument, there are several logical fallacies one can easily
fall into. Some of them are quite tricky, and it's easy to see how one could
fall prey to them oneself, or be sucked into them by others, but there are a
few that there really is no excuse for in polite company.

Argumentum ad ignorantium (to ignorance): i.e., "You haven't proven there
aren't glass tunnels on Mars (UFOs, etc.), therefore Hoagland must be
right."

Argumentum ad hominem (to the man): i.e., "Dickie Hoaxland is a pompous ass
(charlatan, kook, etc.)!" While it is almost always wrong to make an ad
hominem attack, it is perfectly acceptable to say that Hoagland's
"arguments" are kooky, ridiculous, unsubstantiated, etc.

Argumentum tu quoqe (you too): i.e., "Well, so are you, dipstick!" Actually
a better example of this would be, "Well, you (scientists) were wrong about
the Earth being the center of the universe (so you could be wrong about
this)!"

And my own favorite: Argumentum sans testimonium* (without evidence): i.e.,
almost everything Richard Hoagland says.

* actually the Latin word "argumentum" also means proof or evidence, so this
one is from the Department of Redundancy Dept.

Want more? http://www.csun.edu/~dgw61315/fallacies.html