all that and you still aren't impressing anyone with your superior knowledge
Nizkor Project on Fallacies in Arguments.
The site is primarily about the Holocaust, but it has the best rundown of Fallacious Arguments that I've seen, even better than the Logic text I was required to study in order to get an MA in History. You have to try to put together a logical argument when writing a History paper, and one avoiding obvious pitfalls. Unfortunately political discussions abound with these pitfalls. A lot of them are in Latin and date from Roman jurisprudence or Medieval rediscovery of Roman jurisprudence and the study thereof, which was carried out in Latin.
Argumentum ad Hominem. Your argument is not valid because you are a despicable person, or are not worth listening to. There's a lot of this one floating around here.
Argumentum ad hominem tu quoque. Your argument is invalid because you do something that is inconsistent with the argument. Like a smoker advocating non-smoking. Note, it is a fallacy to assert that a smoker's opinion on not smoking is invalid because he smokes.
Appeal to Authority, or Argumentum ad Verecundiam.
It must be true because this or that authority says its true. Hence WMDs. or the use of FoxNews, NewsMax or any of the other tame news sources which follow the Republican, or Administration line.
Appeal to Belief, or to Popularity, or Common Wisdom.
The Bible says ... 85% of the people support the President ... Everybody knows that ... The President's approval rating has fallen to 31% (he still could be right and his opposition wrong)
Appeal to Common Practice.
Everybody cheats a bit on their taxes so ...
Appeal to consequences of a Belief.
The consequences of a belief have no bearing on whether the belief is true or false. "I believe X is true because accepting that X is true has positive consequences." There are about 6 more variations on this belief.
Appeal to emotion. Just look at any political convention and the bounce the party gets after it in the polls. If you vote for me I'll cut your taxes, just because most of the money goes to the top one percent is no reason not to feel happy about it.
Appeal to fear. The argument for the development of the Department of Homeland Security. If we don't do this they will overwhelm us (and just where are those millions of terrorists coming to overwhelm us).
There are also Appeals to Flattery, Novelty, Pity, Popularity, Ridicule, Spite, and Tradition
There is also the Bandwagon effect, which is why reporting is curtailed until the polls are closed in California.
Begging the Question. the premises include the claim that the conclusion is true, or (directly or indirectly) assume that the conclusion is true.
Use of a Biased Sample. Like asking an opinion of something on Speakeasy, the opinion will reflect a conservative bias.
Another common one here, Attacking the Straw Man.
The Straw Man fallacy is committed when a person simply ignores a person's actual position and substitutes or restates it in a distorted, exaggerated or misrepresented version of that position. viz
Person A has position X.
Person B restates position X as position Y
Person B then demolishes position Y.
Therefore X is false/incorrect/flawed.
This sort of "reasoning" is fallacious because attacking a distorted version of a position simply does not constitute an refutation of the position itself.
There are a total of 42 fallacies, which is more than I ever learned, but I think some which are considered here as individual issues were lumped together in my old logic book.
Normally the classic syllogism to prove something involves 3 statements the last of which combines elements of the first 2 into a statement you want to prove or be true. If either of the first 2 statements is false, the conclusion is false.
From the Appeal to Authority:
Person A is (claimed to be) an authority on subject S.
Person A makes claim C about subject S.
Therefore, C is true.
Well, it may be, but just because A is an authority, and he is speaking about his field of expertise he could still be wrong unless he can provide evidence.
Its at least worth a read in order to tone down some of the accusations flying around.