Proof
| Proposition | Derivation |
|---|---|
| Given | |
| Given | |
| Given | |
| Material implication | |
| Hypothetical syllogism | |
| Conjunction | |
| Law of Excluded Middle | |
| Constructive dilemma | |
| Tautology |
Read more about this topic: Disjunction Elimination
Famous quotes containing the word proof:
“A short letter to a distant friend is, in my opinion, an insult like that of a slight bow or cursory salutationa proof of unwillingness to do much, even where there is a necessity of doing something.”
—Samuel Johnson (17091784)
“The source of Pyrrhonism comes from failing to distinguish between a demonstration, a proof and a probability. A demonstration supposes that the contradictory idea is impossible; a proof of fact is where all the reasons lead to belief, without there being any pretext for doubt; a probability is where the reasons for belief are stronger than those for doubting.”
—Andrew Michael Ramsay (16861743)
“The chief contribution of Protestantism to human thought is its massive proof that God is a bore.”
—H.L. (Henry Lewis)