4 ideas
17831 | Cantor gives informal versions of ZF axioms as ways of getting from one set to another [Cantor, by Lake] |
Full Idea: Cantor gives informal versions of the axioms of ZF as ways of getting from one set to another. | |
From: report of George Cantor (Later Letters to Dedekind [1899]) by John Lake - Approaches to Set Theory 1.6 | |
A reaction: Lake suggests that it should therefore be called CZF. |
14283 | A conditional probability does not measure the probability of the truth of any proposition [Lewis, by Edgington] |
Full Idea: Lewis was first to prove this remarkable result: there is no proposition A*B such that, in all probability distributions, p(A*B) = pA(B) [second A a subscript]. A conditional probability does not measure the probability of the truth of any proposition. | |
From: report of David Lewis (Probabilities of Conditionals [1976]) by Dorothy Edgington - Conditionals (Stanf) 3.1 | |
A reaction: The equation says the probability of the combination of A and B is not always the same as the probability of B given A. Bennett refers to this as 'The Equation' in the theory of conditionals. Edgington says a conditional is a supposition and a judgement. |
2614 | Modern phenomenalism holds that objects are logical constructions out of sense-data [Ayer] |
Full Idea: Nowadays phenomenalism is held to be a theory of perception which says that physical objects are logical constructions out of sense-data. | |
From: A.J. Ayer (Phenomenalism [1947], §1) |
2615 | The concept of sense-data allows us to discuss appearances without worrying about reality [Ayer] |
Full Idea: The introduction of the term 'sense-datum' is a means of referring to appearances without prejudging the question of what it is, if anything, that they are appearances of. | |
From: A.J. Ayer (Phenomenalism [1947], §1) |