4 ideas
13827 | Logical consequence isn't a black box (Tarski's approach); we should explain how arguments work [Prawitz] |
Full Idea: Defining logical consequence in the way Tarski does is a rather meagre result, treating an argument as a black box, observing input and output, while disregarding inner structure. We should define logical consequence on the basis of valid arguments. | |
From: Dag Prawitz (On the General Idea of Proof Theory [1974], §2) |
13826 | Model theory looks at valid sentences and consequence, but not how we know these things [Prawitz] |
Full Idea: In model theory, which has dominated the last decades, one concentrates on logically valid sentences, and what follows logically from what, but one disregards questions concerning how we know these things. | |
From: Dag Prawitz (On the General Idea of Proof Theory [1974], §1) |
9464 | One of their own prophets said that Cretans are always liars [Anon (Titus)] |
Full Idea: One of themselves, even a prophet of their own, said, the Cretians are always liars, evil beasts, slow bellies. This witness is true. | |
From: Anon (Titus) (17: Epistle to Titus [c.115], I.12) | |
A reaction: The classic statement of the paradox, the word 'always' being the source of the problem. |
7667 | There are two sides to men - the pleasantly social, and the violent and creative [Diderot, by Berlin] |
Full Idea: Diderot is among the first to preach that there are two men: the artificial man, who belongs in society and seeks to please, and the violent, bold, criminal instinct of a man who wishes to break out (and, if controlled, is responsible for works of genius. | |
From: report of Denis Diderot (works [1769], Ch.3) by Isaiah Berlin - The Roots of Romanticism | |
A reaction: This has an obvious ancestor in Plato's picture (esp. in 'Phaedrus') of the two conflicting sides to the psuché, which seem to be reason and emotion. In Diderot, though, the suppressed man has virtues, which Plato would deny. |