Circular Reasoning and Begging the Question

Some of the subtlest fallacies involve arguments that appear to establish a conclusion but in fact merely assume it. Circular reasoning occurs when the conclusion of an argument is used as one of its premises, and begging the question is its close relative — where the argument assumes, perhaps in different words, the very thing it is supposed to be proving. These fallacies are difficult to spot because the argument can appear logically valid on the surface.

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What Is Circular Reasoning?

Circular reasoning (also called circular argument or petitio principii) occurs when an argument's conclusion is included, explicitly or implicitly, among its premises. The argument goes in a circle: it starts with what it is trying to prove and returns to the same point.

Structure

Component	What happens
Premise	A restatement (often disguised) of the conclusion
Conclusion	The claim that was supposed to be established by the premises
The flaw	No independent reason has been given — the argument assumes what it sets out to prove

Simple Example