9 ideas
| 18200 | Very large sets should be studied in an 'if-then' spirit [Putnam] |
| Full Idea: Sets of a very high type or very high cardinality (higher than the continuum, for example), should today be investigated in an 'if-then' spirit. | |
| From: Hilary Putnam (The Philosophy of Logic [1971], p.347), quoted by Penelope Maddy - Naturalism in Mathematics | |
| A reaction: Quine says the large sets should be regarded as 'uninterpreted'. |
| 18199 | Indispensability strongly supports predicative sets, and somewhat supports impredicative sets [Putnam] |
| Full Idea: We may say that indispensability is a pretty strong argument for the existence of at least predicative sets, and a pretty strong, but not as strong, argument for the existence of impredicative sets. | |
| From: Hilary Putnam (The Philosophy of Logic [1971], p.346), quoted by Penelope Maddy - Naturalism in Mathematics II.2 |
| 8857 | We must quantify over numbers for science; but that commits us to their existence [Putnam] |
| Full Idea: Quantification over mathematical entities is indispensable for science..., therefore we should accept such quantification; but this commits us to accepting the existence of the mathematical entities in question. | |
| From: Hilary Putnam (The Philosophy of Logic [1971], p.57), quoted by Stephen Yablo - Apriority and Existence | |
| A reaction: I'm not surprised that Hartry Field launched his Fictionalist view of mathematics in response to such a counterintuitive claim. I take it we use numbers to slice up reality the way we use latitude to slice up the globe. No commitment to lines! |
| 23674 | If an attempted poisoning results in benefits, we still judge the agent a poisoner [Reid] |
| Full Idea: If a man should give to his neighbour a potion which he really believes will poison him, but which, in the event, proves salutary, and does much good; in moral estimation, he is a poisoner, and not a benefactor. | |
| From: Thomas Reid (Essays on Active Powers 3: Princs of action [1788], 5) | |
| A reaction: I take Reid to mean that morality concerns how we assess the agent, and not the results of his actions. Mill and Bentham concede that we judge people this way, but don't think morality mainly concerns judging people. |
| 23675 | We shouldn't do to others what would be a wrong to us in similar circumstances [Reid] |
| Full Idea: It is a first principle of morals, that we ought not to do to another what we should think wrong to be done to us in like circumstances. | |
| From: Thomas Reid (Essays on Active Powers 3: Princs of action [1788], 6) | |
| A reaction: This negative form of the rule is more plausible than the positive form, presumably because there is more consensus about what we all dislike than what we all prefer. But presents for people that they would like, not that you like. |
| 23672 | To be virtuous, we must care about duty [Reid] |
| Full Idea: A man cannot be virtuous, if he has no regard to duty. | |
| From: Thomas Reid (Essays on Active Powers 3: Princs of action [1788], 5) | |
| A reaction: Thus are Aristotle and Kant united in a simple sentence. Aristotle thinks that a virtuous person thereby sees what is the right thing to do, but I take 'duty' to imply a requirement which comes not from good character but from external society. |
| 23673 | Every worthy man has a principle of honour, and knows what is honourable [Reid] |
| Full Idea: I presume it will be granted, that, in every man of real worth, there is a principle of honour, a regard to what is honourable or dishonourable, very distinct from a regard to his interest. | |
| From: Thomas Reid (Essays on Active Powers 3: Princs of action [1788], 5) | |
| A reaction: Note that there is a 'principle' of honour in a person's character, and there are also actions which are intrinsically honourable or not. I fear that only the worthy are honourable, and only the honourable are worthy! |
| 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. |