Combining Texts

All the ideas for 'Review of Tait 'Provenance of Pure Reason'', 'Letter to Weber' and 'Conceptions of Truth'

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5 ideas

2. Reason / D. Definition / 12. Paraphrase
The idea of 'making' can be mere conceptual explanation (like 'because') [Künne]
     Full Idea: If we say 'being a child of our parent's sibling makes him your first cousin', that can be paraphrased using 'because', and this is the 'because' of conceptual explanation: the second part elucidates the sense of the first part.
     From: Wolfgang Künne (Conceptions of Truth [2003], 3.5.2)
     A reaction: Fans of truth-making are certainly made uncomfortable by talk of 'what makes this a good painting' or 'this made my day'. They need a bit more sharpness to the concept of 'making' a truth.
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 / 3. Nature of Numbers / i. Reals from cuts
I say the irrational is not the cut itself, but a new creation which corresponds to the cut [Dedekind]
     Full Idea: Of my theory of irrationals you say that the irrational number is nothing else than the cut itself, whereas I prefer to create something new (different from the cut), which corresponds to the cut. We have the right to claim such a creative power.
     From: Richard Dedekind (Letter to Weber [1888], 1888 Jan), quoted by Stewart Shapiro - Philosophy of Mathematics 5.4
     A reaction: Clearly a cut will not locate a unique irrational number, so something more needs to be done. Shapiro remarks here that for Dedekind numbers are objects.
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.