6 ideas
| 13766 | 'If' is the same as 'given that', so the degrees of belief should conform to probability theory [Ramsey, by Ramsey] |
| Full Idea: Ramsey suggested that 'if', 'given that' and 'on the supposition that' come to the same thing, and that the degrees of belief in the antecedent should then conform to probability theory. | |
| From: report of Frank P. Ramsey (Truth and Probability [1926]) by Frank P. Ramsey - Law and Causality B | |
| A reaction: [compressed] |
| 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 |
| 19143 | Ramsey gave axioms for an uncertain agent to decide their preferences [Ramsey, by Davidson] |
| Full Idea: Ramsey gave an axiomatic treatment of preference in the face of uncertainty, when applied to a particular agent. | |
| From: report of Frank P. Ramsey (Truth and Probability [1926]) by Donald Davidson - Truth and Predication 2 | |
| A reaction: This is evidently the beginnings of Bayesian decision theory. |
| 3643 | The concept of mind excludes body, and vice versa [Descartes] |
| Full Idea: The concept of body includes nothing at all which belongs to the mind, and the concept of mind includes nothing at all which belongs to the body. | |
| From: René Descartes (Reply to Fourth Objections [1641], 225) | |
| A reaction: A headache? Hunger? The mistake, I think, is to regard the mind as entirely conscious, thus creating a sharp boundary between two aspects of our lives. As shown by blindsight, I take many of my central mental operations to be pre- or non-conscious. |
| 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. |