6 ideas
| 19404 | Necessities rest on contradiction, and contingencies on sufficient reason [Leibniz] |
| Full Idea: The principle of contradiction is the principle of necessity, and the principle that a sufficient reason must be given is the principle of contingency. | |
| From: Gottfried Leibniz (On Sufficient Reason [1686], p.95) | |
| A reaction: [this paragraph is actually undated] Contradictions occur in concrete actuality, as well as in theories and formal systems. If so, then there are necessities in nature. Are they discoverable a posteriori? Leibniz says not. |
| 8090 | Since the language of thought is the same for all, it must be something like logical form [Fodor, by Devlin] |
| Full Idea: Fodor and Jackendorff argue that since the internal language of thought, or conceptual structure, has to be more or less the same for all people, of whatever language, it will surely be something like logical form. | |
| From: report of Jerry A. Fodor (The Language of Thought [1975]) by Keith Devlin - Goodbye Descartes Ch.8 | |
| A reaction: The discovery (by, e.g., Frege and Russell) that there is something called 'logical form', which we can track down and represent in precise and fairly unambiguous symbolism, may be one of the greatest of all human discoveries. Perhaps. |
| 11143 | If concept-learning is hypothesis-testing, that needs innate concepts to get started [Fodor, by Margolis/Laurence] |
| Full Idea: Fodor argues that virtually all lexical concepts are innate, because most models of learning treat concept-learning as hypothesis testing, but that invariably employs the very concept to be learned. | |
| From: report of Jerry A. Fodor (The Language of Thought [1975]) by E Margolis/S Laurence - Concepts 3.3 | |
| A reaction: The obvious response is to reject the theory which gave rise to this difficulty. I take concept formation to be a fairly mechanical and barely conscious response to environment, not a process of fully rational and conscious hypothesising. |
| 13304 | Learned men gain more in one day than others do in a lifetime [Posidonius] |
| Full Idea: In a single day there lies open to men of learning more than there ever does to the unenlightened in the longest of lifetimes. | |
| From: Posidonius (fragments/reports [c.95 BCE]), quoted by Seneca the Younger - Letters from a Stoic 078 | |
| A reaction: These remarks endorsing the infinite superiority of the educated to the uneducated seem to have been popular in late antiquity. It tends to be the religions which discourage great learning, especially in their emphasis on a single book. |
| 19403 | Each of the infinite possible worlds has its own laws, and the individuals contain those laws [Leibniz] |
| Full Idea: As there are an infinity of possible worlds, there are also an infinity of laws, some proper to one, another to another, and each possible individual of any world contains in its own notion the laws of its world. | |
| From: Gottfried Leibniz (On Sufficient Reason [1686], p.95) | |
| A reaction: Hence Leibniz is not really a scientific essentialist, in that he doesn't think the laws arise out of the nature of the matter consituting the world. I wonder if the primitive matter of bodies which attaches to the monads is the same in each world? |
| 20820 | Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus] |
| Full Idea: Posidonius defined time thus: it is an interval of motion, or the measure of speed and slowness. | |
| From: report of Posidonius (fragments/reports [c.95 BCE]) by John Stobaeus - Anthology 1.08.42 | |
| A reaction: Hm. Can we define motion or speed without alluding to time? Looks like we have to define them as a conjoined pair, which means we cannot fully understand either of them. |