display all the ideas for this combination of texts
3 ideas
| 20790 | A proposition is possible if it is true when nothing stops it being true [Stoic school, by Diog. Laertius] |
| Full Idea: That proposition is possible which admits of being true, if external factors do not prevent it from being true, for example, 'Diocles is alive'. | |
| From: report of Stoic school (fragments/reports [c.200 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.75 | |
| A reaction: Well that's different. So every unprevented possibility will occur tomorrow. Any possibility that does not occur tomorrow must have been prevented in some way. Whatever does occur prevents innumerable other things from occurring. Your turn… |
| 15542 | All possibilities are recombinations of properties in the actual world [Armstrong, by Lewis] |
| Full Idea: Armstrong's thesis is that recombination gives all the possibilities there are. There is no 'outer sphere' of possibilities wherein are found new and different universals alien to the actual world. No extra fundamental properties of fundamental particles. | |
| From: report of David M. Armstrong (A Combinatorial Theory of Possibility [1989]) by David Lewis - Armstrong on combinatorial possibility 'Combinatorialism' | |
| A reaction: I can't grasp what Armstrong's basis would be for such a claim. I surmise that current fundamental particles can only have the properties they currently have, but I can't see the impossibility of new stuff with new properties. |
| 20789 | Conditionals are false if the falsehood of the conclusion does not conflict with the antecedent [Stoic school, by Diog. Laertius] |
| Full Idea: A conditional is true if the opposite of the conclusion conflicts with the antecedent, and false if it doesn't conflict. Thus 'If it is day, Dion is walking' is false, because 'Dion is not walking' does not conflict with 'It is day'. | |
| From: report of Stoic school (fragments/reports [c.200 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.73 | |
| A reaction: For the two to conflict there must be some connection in subject matter, which is not the case if the mere falsehood of the conclusion (from a true premise) falsifies the conditional. This seems like a rather good account. |