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Logic
Circular Reasoning
A logical fallacy where the conclusion of an argument is assumed in one of its premises, creating a closed loop of justification.
Also known as *petitio principii* or 'begging the question.' The argument appears valid because its conclusion does follow from its premises — but one of those premises is the conclusion itself, either explicitly or in disguised form.
**Example:** 'The Bible is true because it is the Word of God, and we know it is the Word of God because the Bible says so.'
In Agrippa's Trilemma, circular reasoning is one of the three failure modes. A worldview whose argument chain loops back to its own starting premise has not provided genuine justification.