diallelous

adj

diallelous

adj

Etymology From diallel + -ous.

1

Human sciences, Philosophy, Sciences Involving circular reasoning.

Saying skydiving is unsafe because it's dangerous and then saying it's dangerous because it's unsafe is diallelous.
Diallelous. […] What is generally called defining reasoning in a circle.1878, Francis Garden, A Dictionary of English Philosophical Terms, page 46:

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