Formal Deductive Fallacies and Informal Fallacies
Formal fallacies of deductive reasoning fail to follow the rules of logic that guarantee a true conclusion follows given the truth of the premises. This is said to render the argument invalid.
Inductive fallacies are not formal in this sense. Their merit is judged in terms of rational persuasiveness, inductive strength or methodology (for example, statistical inference). For instance, the fallacy of hasty generalization, can be roughly stated as an invalid syllogism:
- A is an X
- A is also a Y
- Therefore, all Xs are also Ys
While never a valid deduction, if such an inference can made on statistical grounds, it may nonetheless be convincing.
Read more about this topic: Informal Fallacy
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