Circular reasoning
Circular reasoning (
Latin:
circulus in probando, "circle in proving"; also known as
circular logic) is a
logical fallacy in which
the reasoner begins with what they are trying to end with.[1] The components of a circular argument are often logically
valid because if the premises are true, the conclusion must be true.
Circular reasoning is not a formal logical fallacy but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade. Other ways to express this are that there is no reason to accept the premises unless one already believes the conclusion, or that the premises provide no independent ground or evidence for the conclusion.
[2] Begging the question is closely related to circular reasoning, and in modern usage the two generally refer to the same thing.
[3]
https://en.wikipedia.org/wiki/Circular_reasoning