15.1: What Is a Fallacy?
- Page ID
- 199368
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The final step in checking the strength of reasoning is to make sure there are no fallacies in our reasoning. Often, correcting for fallacies is the missing piece to creating and evaluating logical arguments. A fallacy is an error in reasoning. A fallacy indicates there is a problem with the logic of deductive or inductive reasoning. This differs from a factual error, which is simply being wrong about the facts. To be more specific, a fallacy is an “argument” in which the premises given for the conclusion do not provide the needed degree of support. A fallacy is a mistake in the way that the final conclusion of the argument, or any intermediate conclusions, are logically related to their supporting premises. When there is a fallacy in an argument, the argument is said to be unsound or invalid
The presence of a logical fallacy in an argument does not necessarily imply anything about the argument’s premises or its conclusion. Both may actually be correct, but the argument is still invalid because the conclusion does not follow from the premises using the inference principles of the argument. Recognizing fallacies is often difficult, and indeed fallacious arguments often persuade their intended audience. Detecting and avoiding fallacious reasoning will at least prevent adoption of some erroneous conclusions.