Combining Texts

All the ideas for 'Reply to Foucher', 'Review of Tait 'Provenance of Pure Reason'' and 'The Nature of Existence vol.1'

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5 ideas

4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The old problems with the axiom of choice are probably better ascribed to the law of excluded middle [Parsons,C]
     Full Idea: The difficulties historically attributed to the axiom of choice are probably better ascribed to the law of excluded middle.
     From: Charles Parsons (Review of Tait 'Provenance of Pure Reason' [2009], §2)
     A reaction: The law of excluded middle was a target for the intuitionists, so presumably the debate went off in that direction.
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
I strongly believe in the actual infinite, which indicates the perfections of its author [Leibniz]
     Full Idea: I am so much for the actual infinite that instead of admitting that nature abhors it, as is commonly said, I hold that it affects nature everywhere in order to indicate the perfections of its author.
     From: Gottfried Leibniz (Reply to Foucher [1693], p.99)
     A reaction: I would have thought that, for Leibniz, while infinities indicate the perfections of their author, that is not the reason why they exist. God wasn't, presumably, showing off. Leibniz does not think we can actually know these infinities.
6. Mathematics / C. Sources of Mathematics / 8. Finitism
If functions are transfinite objects, finitists can have no conception of them [Parsons,C]
     Full Idea: The finitist may have no conception of function, because functions are transfinite objects.
     From: Charles Parsons (Review of Tait 'Provenance of Pure Reason' [2009], §4)
     A reaction: He is offering a view of Tait's. Above my pay scale, but it sounds like a powerful objection to the finitist view. Maybe there is a finitist account of functions that could be given?
7. Existence / D. Theories of Reality / 11. Ontological Commitment / e. Ontological commitment problems
If a mathematical structure is rejected from a physical theory, it retains its mathematical status [Parsons,C]
     Full Idea: If experience shows that some aspect of the physical world fails to instantiate a certain mathematical structure, one will modify the theory by sustituting a different structure, while the original structure doesn't lose its status as part of mathematics.
     From: Charles Parsons (Review of Tait 'Provenance of Pure Reason' [2009], §2)
     A reaction: This seems to be a beautifully simple and powerful objection to the Quinean idea that mathematics somehow only gets its authority from physics. It looked like a daft view to begin with, of course.
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
Substance has to exist, with no intrinsic qualities or relations [McTaggart]
     Full Idea: Something must exist, then, and have qualities, without being itself either a quality or a relation. And this is Substance.
     From: J.M.E. McTaggart (The Nature of Existence vol.1 [1921], §67), quoted by R.D. Ingthorsson - A Powerful Particulars View of Causation 7.2
     A reaction: Ingthorsson quotes this as 'the most extreme analytic view', which is a long way from the Aristotelian view. This is the implausible bare substrate.