41 ideas
| 501 | Reason is a more powerful persuader than gold [Democritus (attr)] |
| 7786 | Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [Girle] |
| 7798 | There are three axiom schemas for propositional logic [Girle] |
| 7799 | Proposition logic has definitions for its three operators: or, and, and identical [Girle] |
| 7797 | Axiom systems of logic contain axioms, inference rules, and definitions of proof and theorems [Girle] |
| 7794 | There are seven modalities in S4, each with its negation [Girle] |
| 7793 | ◊p → □◊p is the hallmark of S5 [Girle] |
| 7795 | S5 has just six modalities, and all strings can be reduced to those [Girle] |
| 7787 | Possible worlds logics use true-in-a-world rather than true [Girle] |
| 7788 | Modal logic has four basic modal negation equivalences [Girle] |
| 7796 | Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle] |
| 7789 | Necessary implication is called 'strict implication'; if successful, it is called 'entailment' [Girle] |
| 7790 | If an argument is invalid, a truth tree will indicate a counter-example [Girle] |
| 7800 | Analytic truths are divided into logically and conceptually necessary [Girle] |
| 7801 | Possibilities can be logical, theoretical, physical, economic or human [Girle] |
| 7792 | A world has 'access' to a world it generates, which is important in possible worlds semantics [Girle] |
| 514 | Beauty is merely animal without intelligence [Democritus (attr)] |
| 525 | Behave well when alone, and feel shame in you own eyes [Democritus (attr)] |
| 502 | Good breeding in men means having a good character [Democritus (attr)] |
| 507 | Virtuous love consists of decorous desire for the beautiful [Democritus (attr)] |
| 521 | We should only choose pleasures which are concerned with the beautiful [Democritus (attr)] |
| 505 | Good and true are the same for everyone, but pleasures differ [Democritus (attr)] |
| 508 | Only accept beneficial pleasures [Democritus (attr)] |
| 520 | The great pleasures come from the contemplation of noble works [Democritus (attr)] |
| 522 | Moderation brings more pleasures, and so increases pleasure [Democritus (attr)] |
| 506 | Immoderate desire is the mark of a child, not an adult [Democritus (attr)] |
| 523 | It is as brave to master pleasure as to overcome the enemy [Democritus (attr)] |
| 503 | Virtue doesn't just avoid evil, but also doesn't desire it [Democritus (attr)] |
| 518 | A bad life is just a drawn-out death [Democritus (attr)] |
| 497 | Be virtuous from duty, not from fear [Democritus (attr)] |
| 499 | Repentance of shameful deeds is salvation [Democritus (attr)] |
| 524 | Virtue comes more from practice than from nature [Democritus (attr)] |
| 519 | One must avoid even speaking of evil deeds [Democritus (attr)] |
| 500 | The wrongdoer is more unfortunate than the person wronged [Democritus (attr)] |
| 1539 | The endless desire for money is a crueller slavery than poverty [Democritus (attr)] |
| 526 | Small appetite makes poverty equal to wealth [Democritus (attr)] |
| 511 | It is better to have one intelligent friend than many unintelligent [Democritus (attr)] |
| 498 | It is a great thing, when one is in adversity, to think of duty [Democritus (attr)] |
| 1541 | It is better to be poor in a democracy than be rich without freedom [Democritus (attr)] |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |