Circular reasoning is using your conclusion as one of your reasons. Fall into circular reasoning.
It can be perfectly valid and still prove nothing, which is what makes it slippery. Circular reasoning is hardest to see when the circle is large enough to take a page.
1nouncircular reasoningUsing your conclusion as one of your reasons.
“The argument was circular reasoning stretched over four paragraphs.”
circular reasoning is a fallacy.
Practised in Logic & Argument