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Ideas for 'Universal Prescriptivism', 'The Making of a Philosopher' and 'Introduction to Mathematical Philosophy'

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10 ideas

5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
All the propositions of logic are completely general [Russell]
     Full Idea: It is part of the definition of logic that all its propositions are completely general.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XV)
5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
In modern times, logic has become mathematical, and mathematics has become logical [Russell]
     Full Idea: Logic has become more mathematical, and mathematics has become more logical. The consequence is that it has now become wholly impossible to draw a line between the two; in fact, the two are one.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVIII)
     A reaction: This appears to be true even if you reject logicism about mathematics. Logicism is sometimes rejected because it always ends up with a sneaky ontological commitment, but maybe mathematics shares exactly the same commitment.
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Logic can only assert hypothetical existence [Russell]
     Full Idea: No proposition of logic can assert 'existence' except under a hypothesis.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVIII)
     A reaction: I am prepared to accept this view fairly dogmatically, though Musgrave shows some of the difficulties of the if-thenist view (depending on which 'order' of logic is being used).
Logic is concerned with the real world just as truly as zoology [Russell]
     Full Idea: Logic is concerned with the real world just as truly as zoology, though with its more abstract and general features.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVI)
     A reaction: I love this idea and am very sympathetic to it. The rival view seems to be that logic is purely conventional, perhaps defined by truth tables etc. It is hard to see how a connective like 'tonk' could be self-evidently silly if it wasn't 'unnatural'.
Logic can be known a priori, without study of the actual world [Russell]
     Full Idea: Logical propositions are such as can be known a priori, without study of the actual world.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVIII)
     A reaction: This remark constrasts strikingly with Idea 12444, which connects logic to the actual world. Is it therefore a priori synthetic?
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Asking 'Did Homer exist?' is employing an abbreviated description [Russell]
     Full Idea: When we ask whether Homer existed, we are using the word 'Homer' as an abbreviated description.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVI)
     A reaction: It is hard to disagree with Russell over this rather unusual example. It doesn't seem so plausible when Ottiline refers to 'Bertie'.
Russell admitted that even names could also be used as descriptions [Russell, by Bach]
     Full Idea: Russell clearly anticipated Donnellan when he said proper names can also be used as descriptions, adding that 'there is nothing in the phraseology to show whether they are being used in this way or as names'.
     From: report of Bertrand Russell (Introduction to Mathematical Philosophy [1919], p.175) by Kent Bach - What Does It Take to Refer? 22.2 L1
     A reaction: This seems also to anticipate Strawson's flexible and pragmatic approach to these things, which I am beginning to think is correct.
Names are really descriptions, except for a few words like 'this' and 'that' [Russell]
     Full Idea: We can even say that, in all such knowledge as can be expressed in words, with the exception of 'this' and 'that' and a few other words of which the meaning varies on different occasions - no names occur, but what seem like names are really descriptions.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVI)
     A reaction: I like the caveat about what is expressed in words. Russell is very good at keeping non-verbal thought in the picture. This is his famous final reduction of names to simple demonstratives.
5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
The only genuine proper names are 'this' and 'that' [Russell]
     Full Idea: In all knowledge that can be expressed in words - with the exception of "this" and "that", and a few other such words - no genuine proper names occur, but what seem like genuine proper names are really descriptions
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVI)
     A reaction: This is the terminus of Russell's train of thought about descriptions. Suppose you point to something non-existent, like a ghost in a misty churchyard? You'd be back to the original problem of naming a non-existent!
5. Theory of Logic / F. Referring in Logic / 2. Descriptions / a. Descriptions
'I met a unicorn' is meaningful, and so is 'unicorn', but 'a unicorn' is not [Russell]
     Full Idea: In 'I met a unicorn' the four words together make a significant proposition, and the word 'unicorn' is significant, …but the two words 'a unicorn' do not form a group having a meaning of its own. It is an indefinite description describing nothing.
     From: Bertrand Russell (Introduction to Mathematical Philosophy [1919], XVI)