Combining Texts

All the ideas for 'A Puzzle about Belief', 'The Theory of Knowledge' and 'Opus Maius (major works)'

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6 ideas

5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
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.
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.
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
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'
7. Existence / D. Theories of Reality / 8. Facts / d. Negative facts
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).
18. Thought / B. Mechanics of Thought / 5. Mental Files
Puzzled Pierre has two mental files about the same object [Recanati on Kripke]
     Full Idea: In Kripke's puzzle about belief, the subject has two distinct mental files about one and the same object.
     From: comment on Saul A. Kripke (A Puzzle about Belief [1979]) by François Recanati - Mental Files 17.1
     A reaction: [Pierre distinguishes 'London' from 'Londres'] The Kripkean puzzle is presented as very deep, but I have always felt there was a simple explanation, and I suspect that this is it (though I will leave the reader to think it through, as I'm very busy…).
26. Natural Theory / D. Laws of Nature / 8. Scientific Essentialism / d. Knowing essences
No one even knows the nature and properties of a fly - why it has that colour, or so many feet [Bacon,R]
     Full Idea: No one is so wise regarding the natural world as to know with certainty all the truths that concern the nature and properties of a single fly, or to know the proper causes of its color and why it has so many feet, neither more nor less.
     From: Roger Bacon (Opus Maius (major works) [1254], I.10), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 23.6
     A reaction: Pasnau quotes this in the context of 'occult' qualities. It is scientific essentialism, because Bacon clearly takes it that the explanation of these things would be found within the essence of the fly, if we could only get at it.