18 ideas
| 9108 | From an impossibility anything follows [William of Ockham] |
| 2661 | Dialectic is speech cast in the form of logical argument [Cicero] |
| 2673 | There cannot be more than one truth [Cicero] |
| 9107 | A proposition is true if its subject and predicate stand for the same thing [William of Ockham] |
| 16300 | Ockham had an early axiomatic account of truth [William of Ockham, by Halbach] |
| 2669 | Dialectic assumes that all statements are either true or false, but self-referential paradoxes are a big problem [Cicero] |
| 9106 | The word 'every' only signifies when added to a term such as 'man', referring to all men [William of Ockham] |
| 9113 | Just as unity is not a property of a single thing, so numbers are not properties of many things [William of Ockham] |
| 9110 | The words 'thing' and 'to be' assert the same idea, as a noun and as a verb [William of Ockham] |
| 15388 | Universals are single things, and only universal in what they signify [William of Ockham] |
| 9109 | If essence and existence were two things, one could exist without the other, which is impossible [William of Ockham] |
| 2664 | If we have complete healthy senses, what more could the gods give us? [Cicero] |
| 2665 | How can there be a memory of what is false? [Cicero] |
| 20800 | Every true presentation can have a false one of the same quality [Cicero] |
| 9105 | Some concepts for propositions exist only in the mind, and in no language [William of Ockham] |
| 20721 | Punctuality and justice in dealings are excellent for raising a man in the world [Franklin] |
| 2672 | Virtues must be very detached, to avoid being motivated by pleasure [Cicero] |
| 20720 | Time is money, ..credit is money, ..and money breeds more money [Franklin] |