8 ideas
| 23025 | Philosophers should be more inductive, and test results by their conclusions, not their self-evidence [Russell] |
| Full Idea: The progress of philosophy seems to demand that, like science, it should learn to practise induction, to test its premisses by the conclusions to which they lead, and not merely by their apparent self-evidence. | |
| From: Bertrand Russell (Explanations in reply to Mr Bradley [1899], nr end) | |
| A reaction: [from Twitter] Love this. It is 'one person's modus ponens is another person's modus tollens'. I think all philosophical conclusions, without exception, should be reached by evaluating the final result fully, and not just following a line of argument. |
| 15642 | If kinds depend only on what can be observed, many underlying essences might produce the same kind [Eagle] |
| Full Idea: If the kinds there are depend not on the essences of the objects but on their observed distinguishing particulars, ...then for any kind that we think there is, it is possible that there are many underlying essences which are observably indistinguishable. | |
| From: Antony Eagle (Locke on Essences and Kinds [2005], IV) | |
| A reaction: Eagle is commenting on Locke's reliance on nominal essences. This seems to be the genuine problem with jadeite and nephrite (both taken to be 'jade'), or with 'fool's gold'. This isn't an objection to Locke; it just explains the role of science. |
| 15645 | Nominal essence are the observable properties of things [Eagle] |
| Full Idea: It is clear the nominal essences really are the properties of the things which have them: they are (a subset of) the observable properties of the things. | |
| From: Antony Eagle (Locke on Essences and Kinds [2005], IV) | |
| A reaction: I think this is wrong. The surface characteristics are all that is available to us, so our classifications must be based on those, but it is on the ideas of them, not their intrinsic natures. That is empiricsm! What makes the properties 'essential'? |
| 15643 | Nominal essence mistakenly gives equal weight to all underlying properties that produce appearances [Eagle] |
| Full Idea: Nominal essence does not allow for gradations in significance for the underlying properties. Those are all essential for the object behaving as it observably does, and they must all be given equal weight when deciding what the object does. | |
| From: Antony Eagle (Locke on Essences and Kinds [2005], IV) | |
| A reaction: This is where 'scientific' essentialism comes in. If we take one object, or one kind of object, in isolation, Eagle is right. When we start to compare, and to set up controlled conditions tests, we can dig into the 'gradations' he cares about. |
| 3597 | Foundations need not precede other beliefs [Wittgenstein] |
| Full Idea: I do not explicitly learn the propositions that stand fast for me. I can discover them subsequently like the axis around which a body rotates. | |
| From: Ludwig Wittgenstein (On Certainty [1951], §152), quoted by Michael Williams - Problems of Knowledge Ch.14 | |
| A reaction: A nice metaphor for the way in which axioms are derived. It is also close to Quine's metaphor of the 'net' of understanding, with the centre area 'standing fast'. Not neat and tidy, though. |
| 3596 | Total doubt can't even get started [Wittgenstein, by Williams,M] |
| Full Idea: Wittgenstein remarked that if you tried to doubt everything, you would not get as far as doubting anything. | |
| From: report of Ludwig Wittgenstein (On Certainty [1951]) by Michael Williams - Problems of Knowledge Ch.14 |
| 4721 | If you are not certain of any fact, you cannot be certain of the meaning of your words either [Wittgenstein] |
| Full Idea: If you are not certain of any fact, you cannot be certain of the meaning of your words either. | |
| From: Ludwig Wittgenstein (On Certainty [1951], §114) | |
| A reaction: A wonderfully challenging aphorism. I suspect that it is true, but not really a problem. We all know the meaning of 'Loch Ness Monster', as long as we don't get too fussy. And for local objects I am happy that I know the facts. |
| 15641 | Kinds are fixed by the essential properties of things - the properties that make it that kind of thing [Eagle] |
| Full Idea: The natural thought is to think that real kinds are given only by classification on the basis of essential properties: properties that make an object the kind of thing that it is. | |
| From: Antony Eagle (Locke on Essences and Kinds [2005], II) | |
| A reaction: Circularity alert! Circularity alert! Essence gives a thing its kind - and hence we can see what the kind is? Test for a trivial property! Eagle is not unaware of these issues. Does he mean 'necessary' rather than 'essential'? |