7 ideas
23476 | Logical constants seem to be entities in propositions, but are actually pure form [Russell] |
Full Idea: 'Logical constants', which might seem to be entities occurring in logical propositions, are really concerned with pure form, and are not actually constituents of the propositions in the verbal expressions of which their names occur. | |
From: Bertrand Russell (The Theory of Knowledge [1913], 1.IX) | |
A reaction: This seems to entirely deny the existence of logical constants, and yet he says that they are named. Russell was obviously under pressure here from Wittgenstein. |
23477 | We use logical notions, so they must be objects - but I don't know what they really are [Russell] |
Full Idea: Such words as or, not, all, some, plainly involve logical notions; since we use these intelligently, we must be acquainted with the logical objects involved. But their isolation is difficult, and I do not know what the logical objects really are. | |
From: Bertrand Russell (The Theory of Knowledge [1913], 1.IX) | |
A reaction: See Idea 23476, from the previous page. Russell is struggling. Wittgenstein was telling him that the constants are rules (shown in truth tables), rather than objects. |
18273 | Logical truths are known by their extreme generality [Russell] |
Full Idea: A touchstone by which logical propositions may be distinguished from all others is that they result from a process of generalisation which has been carried to its utmost limits. | |
From: Bertrand Russell (The Theory of Knowledge [1913], p.129), quoted by J. Alberto Coffa - The Semantic Tradition from Kant to Carnap 7 'What' |
22315 | There can't be a negative of a complex, which is negated by its non-existence [Potter on Russell] |
Full Idea: On Russell's pre-war conception it is obvious that a complex cannot be negative. If a complex were true, what would make it false would be its non-existence, not the existence of some other complex. | |
From: comment on Bertrand Russell (The Theory of Knowledge [1913]) by Michael Potter - The Rise of Analytic Philosophy 1879-1930 41 'Neg' | |
A reaction: It might be false because it doesn't exist, but also 'made' false by a rival complex (such as Desdemona loving Othello). |
579 | Cratylus said you couldn't even step into the same river once [Cratylus, by Aristotle] |
Full Idea: Cratylus was appalled that Heraclitus said you could not step twice into the same river, because it was already going too far to admit stepping into the same river once. | |
From: report of Cratylus (fragments/reports [c.425 BCE]) by Aristotle - Metaphysics 1010a | |
A reaction: Compare Idea 427. |
578 | Cratylus decided speech was hopeless, and his only expression was the movement of a finger [Cratylus, by Aristotle] |
Full Idea: Cratylus thought speech of any kind was radically inappropriate and that expression should be restricted exclusively to the movement of the finger. | |
From: report of Cratylus (fragments/reports [c.425 BCE]) by Aristotle - Metaphysics 1010a |
16362 | An identity statement aims at getting the hearer to merge two mental files [Lockwood] |
Full Idea: The purpose of an identity statement is to get the hearer to merge these files or bodies of information into one. | |
From: Michael Lockwood (Identity and Reference [1971], p.209), quoted by François Recanati - Mental Files 4.1 | |
A reaction: Lockwood is a pioneer, in seeing 'Hesperus is Phosphorus' and 'Scott is the author of 'Waverley'' in terms of how the mind works. Mental files seem to me to explain a huge amount. Recanati proposes 'linking' rather than 'merging'. |