### What is *proof*?

### What is *proof*?

- The validation of a proposition by application of specified rules, as of induction or deduction, to assumptions, axioms, and sequentially derived conclusions.
- Convincing or persuasive demonstration: was asked for proof of his identity; an employment history that was proof of her dependability.
- Fully or successfully resistant; impervious. Often used in combination: waterproof watches; a fireproof cellar door.