8 ideas
| 13099 | Analysing right down to primitive concepts seems beyond our powers [Leibniz] |
| Full Idea: An analysis of concepts such that we can reach primitive concepts...does not seem to be within human power. | |
| From: Gottfried Leibniz (Introduction to a Secret Encyclopaedia [1679], C513-14), quoted by Cover,J/O'Leary-Hawthorne,J - Substance and Individuation in Leibniz | |
| A reaction: Leibniz is nevertheless fully committed, I think, to the existence of such primitives, and is in the grip of the rationalist dream that thoughts can become completely clear, and completely well-founded. |
| 5022 | We hold a proposition true if we are ready to follow it, and can't see any objections [Leibniz] |
| Full Idea: A proposition is held to be true by us when our mind is ready to follow it and no reason for doubting it can be found. | |
| From: Gottfried Leibniz (Introduction to a Secret Encyclopaedia [1679], p.7) | |
| A reaction: This follows on from Descartes' view, but it now sounds more like psychology than metaphysics. Clearly a false proposition could fit this desciption. Personally I follow propositions to which I can see no objection, without actually holding them true. |
| 5998 | From the necessity of the past we can infer the impossibility of what never happens [Diod.Cronus, by White,MJ] |
| Full Idea: Diodorus' Master Argument inferred that since what is past (i.e. true in the past) is necessary, and the impossible cannot follow from the possible, that therefore if something neither is nor ever will be the case, then it is impossible. | |
| From: report of Diodorus Cronus (fragments/reports [c.300 BCE]) by Michael J. White - Diodorus Cronus | |
| A reaction: The argument is, apparently, no longer fully clear, but it seems to imply determinism, or at least a rejection of the idea that free will and determinism are compatible. (Epictetus 2.19) |
| 20832 | The Master Argument seems to prove that only what will happen is possible [Diod.Cronus, by Epictetus] |
| Full Idea: The Master Argument: these conflict 1) what is past and true is necessary, 2) the impossible does not follow from the possible, 3) something possible neither is nor will be true. Hence only that which is or will be true is possible. | |
| From: report of Diodorus Cronus (fragments/reports [c.300 BCE]) by Epictetus - The Discourses 2.19.1 | |
| A reaction: [Epictetus goes on to discuss views about which of the three should be given up] It is possible there will be a sea fight tomorrow; tomorrow comes, and no sea fight; so there was necessarily no sea fight; so the impossible followed from the possible. |
| 14304 | Conditionals are true when the antecedent is true, and the consequent has to be true [Diod.Cronus] |
| Full Idea: The connected (proposition) is true when it begins with true and neither could nor can end with false. | |
| From: Diodorus Cronus (fragments/reports [c.300 BCE]), quoted by Stephen Mumford - Dispositions 03.4 | |
| A reaction: [Mumford got the quote from Bochenski] This differs from the truth-functional account because it says nothing about when the antecedent is false, which fits in also with the 'supposition' view, where A is presumed. This idea adds necessity. |
| 6024 | Thought is unambiguous, and you should stick to what the speaker thinks they are saying [Diod.Cronus, by Gellius] |
| Full Idea: No one says or thinks anything ambiguous, and nothing should be held to be being said beyond what the speaker thinks he is saying. | |
| From: report of Diodorus Cronus (fragments/reports [c.300 BCE]) by Aulus Gellius - Noctes Atticae 11.12.2 | |
| A reaction: A key argument in favour of propositions, implied in this remark, is that propositions are never ambiguous, though the sentences expressing them may be |
| 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. |