10 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) |
| 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) |
| 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. |
| 23218 | The brain has no responsibility for sensations, which occur in the heart [Aristotle] |
| Full Idea: And of course, the brain is not responsible for any of the sensations at all. The correct view is that the seat and source of sensation is the region of the heart. | |
| From: Aristotle (The Parts of Animals [c.345 BCE]), quoted by Matthew Cobb - The Idea of the Brain 1 | |
| A reaction: [Need a reference] Hippocrates's assertion a century earlier made no impression on the great man. I wish he had been a little more circumspect with his own view. |
| 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) |
| 1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
| Full Idea: Archelaus was the first person to say that the universe is boundless. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
| 5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
| Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
| From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
| A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |