Proof
| Proposition | Derivation |
|---|---|
| Given | |
| Given | |
| Material implication | |
| Modus ponens |
| Proposition | Derivation |
|---|---|
| Given | |
| Given | |
| Material implication | |
| Transposition | |
| Modus ponens |
Read more about this topic: Disjunctive Syllogism
Famous quotes containing the word proof:
“He who has never failed somewhere, that man can not be great. Failure is the true test of greatness. And if it be said, that continual success is a proof that a man wisely knows his powers,it is only to be added, that, in that case, he knows them to be small.”
—Herman Melville (18191891)
“If some books are deemed most baneful and their sale forbid, how, then, with deadlier facts, not dreams of doting men? Those whom books will hurt will not be proof against events. Events, not books, should be forbid.”
—Herman Melville (18191891)
“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)