11 ideas
| 2661 | Dialectic is speech cast in the form of logical argument [Cicero] |
| Full Idea: Dialectic is speech cast in the form of logical argument. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], I.viii.32) |
| 2673 | There cannot be more than one truth [Cicero] |
| Full Idea: There cannot be more than one truth. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.xlviii.147) |
| 19370 | 'Blind thought' is reasoning without recognition of the ingredients of the reasoning [Leibniz, by Arthur,R] |
| Full Idea: Leibniz invented the concept of 'blind thought' - reasoning by a manipulation of characters without being able to recognise what each character stands for. | |
| From: report of Gottfried Leibniz (Towards a Universal Characteristic [1677]) by Richard T.W. Arthur - Leibniz |
| 2669 | Dialectic assumes that all statements are either true or false, but self-referential paradoxes are a big problem [Cicero] |
| Full Idea: It is a fundamental principle of dialectic that every statement is either true or false. So is this a true proposition or a false one: "If you say that you are lying and say it truly, you lie"? | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.xxix.95) |
| 19391 | We can assign a characteristic number to every single object [Leibniz] |
| Full Idea: The true principle is that we can assign to every object its determined characteristic number. | |
| From: Gottfried Leibniz (Towards a Universal Characteristic [1677], p.18) | |
| A reaction: I add this as a predecessor of Gödel numbering. It is part of Leibniz's huge plan for a Universal Characteristic, to map reality numerically, and then calculate the truths about it. Gödel seems to allow metaphysics to be done mathematically. |
| 19390 | Everything is subsumed under number, which is a metaphysical statics of the universe, revealing powers [Leibniz] |
| Full Idea: There is nothing which is not subsumable under number; number is therefore a fundamental metaphysical form, and arithmetic a sort of statics of the universe, in which the powers of things are revealed. | |
| From: Gottfried Leibniz (Towards a Universal Characteristic [1677], p.17) | |
| A reaction: I take numbers to be a highly generalised and idealised description of an aspect of reality (seen as mainly constituted by countable substances). Seeing reality as processes doesn't lead us to number. So I like this idea. |
| 490 | Everything happens by reason and necessity [Leucippus] |
| Full Idea: Nothing happens at random; everything happens out of reason and by necessity. | |
| From: Leucippus (fragments/reports [c.435 BCE], B002), quoted by (who?) - where? |
| 2664 | If we have complete healthy senses, what more could the gods give us? [Cicero] |
| Full Idea: If human nature were interrogated by some god as to whether it was content with its own senses in a sound and undamaged state or demanded something better, I cannot see what more it could ask for. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.vii.19) |
| 2665 | How can there be a memory of what is false? [Cicero] |
| Full Idea: How can there possibly be a memory of what is false? | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.vii.22) |
| 20800 | Every true presentation can have a false one of the same quality [Cicero] |
| Full Idea: [The sceptical Academics say] what is false cannot be perceived, but every true presentation is such that there can be a false presentation of the same quality. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.40) | |
| A reaction: It was the stoics who focused the discussion on 'presentations'. This claim is purely theoretical; no one has ever experienced a false presentation of talking to a family member that was as vivid as the real thing. |
| 2672 | Virtues must be very detached, to avoid being motivated by pleasure [Cicero] |
| Full Idea: None of the virtues can exist unless they are disinterested, for virtue driven to duty by pleasure as a sort of pay is not virtue at all but a deceptive sham and pretence of virtue. | |
| From: M. Tullius Cicero (Academica [c.45 BCE], II.xlvi.140) |