This is an excellent introduction to deductive logic, inductive logic, and logical fallacies. When I was in college I took a course on symbolic logic. It did me less good than this website. This gives good information to use in forum debates (which all too often become insult contests.

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A deductive argument is an argument such that the premises provide (or appear to provide) complete support for the conclusion...

A good deductive argument is known as a valid argument and is such that if all its premises are true, then its conclusion must be true...

A good inductive argument is known as a strong (or "cogent") inductive argument. It is such that if the premises are true, the conclusion is likely to be true...

A fallacy is, very generally, an error in reasoning. This differs from a factual error, which is simply being wrong about the facts.

http://www.nizkor.org/features/fallacies/
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In political and religious arguments most reasoning seems to be inductive.