38 ideas
| 354 | Wisdom makes virtue and true goodness possible [Plato] |
| 370 | Philosophy is a purification of the soul ready for the afterlife [Plato] |
| 350 | In investigation the body leads us astray, but the soul gets a clear view of the facts [Plato] |
| 362 | The greatest misfortune for a person is to develop a dislike for argument [Plato] |
| 10775 | The axiom of choice now seems acceptable and obvious (if it is meaningful) [Tharp] |
| 10766 | Logic is either for demonstration, or for characterizing structures [Tharp] |
| 10767 | Elementary logic is complete, but cannot capture mathematics [Tharp] |
| 10769 | Second-order logic isn't provable, but will express set-theory and classic problems [Tharp] |
| 10762 | In sentential logic there is a simple proof that all truth functions can be reduced to 'not' and 'and' [Tharp] |
| 10776 | The main quantifiers extend 'and' and 'or' to infinite domains [Tharp] |
| 10774 | There are at least five unorthodox quantifiers that could be used [Tharp] |
| 10777 | Skolem mistakenly inferred that Cantor's conceptions were illusory [Tharp] |
| 10773 | The Löwenheim-Skolem property is a limitation (e.g. can't say there are uncountably many reals) [Tharp] |
| 10765 | Soundness would seem to be an essential requirement of a proof procedure [Tharp] |
| 10763 | Completeness and compactness together give axiomatizability [Tharp] |
| 10770 | If completeness fails there is no algorithm to list the valid formulas [Tharp] |
| 10771 | Compactness is important for major theories which have infinitely many axioms [Tharp] |
| 10772 | Compactness blocks infinite expansion, and admits non-standard models [Tharp] |
| 10764 | A complete logic has an effective enumeration of the valid formulas [Tharp] |
| 10768 | Effective enumeration might be proved but not specified, so it won't guarantee knowledge [Tharp] |
| 13155 | If you add one to one, which one becomes two, or do they both become two? [Plato] |
| 21347 | If Simmias is taller than Socrates, that isn't a feature that is just in Simmias [Plato] |
| 360 | We must have a prior knowledge of equality, if we see 'equal' things and realise they fall short of it [Plato] |
| 1 | There is only one source for all beauty [Plato] |
| 368 | Other things are named after the Forms because they participate in them [Plato] |
| 16516 | The ship which Theseus took to Crete is now sent to Delos crowned with flowers [Plato] |
| 357 | People are obviously recollecting when they react to a geometrical diagram [Plato] |
| 359 | If we feel the inadequacy of a resemblance, we must recollect the original [Plato] |
| 9343 | To achieve pure knowledge, we must get rid of the body and contemplate things with the soul [Plato] |
| 15859 | To investigate the causes of things, study what is best for them [Plato] |
| 13154 | Do we think and experience with blood, air or fire, or could it be our brain? [Plato] |
| 364 | One soul can't be more or less of a soul than another [Plato] |
| 468 | Musical performance can reveal a range of virtues [Damon of Ath.] |
| 361 | It is a mistake to think that the most violent pleasure or pain is therefore the truest reality [Plato] |
| 351 | War aims at the acquisition of wealth, because we are enslaved to the body [Plato] |
| 13156 | Fancy being unable to distinguish a cause from its necessary background conditions! [Plato] |
| 369 | If the Earth is spherical and in the centre, it is kept in place by universal symmetry, not by force [Plato] |
| 363 | Whether the soul pre-exists our body depends on whether it contains the ultimate standard of reality [Plato] |