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Ideas for 'works (fragments)', 'Philosophy of Mathematics' and 'Sickness unto Death'

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8 ideas

6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
We distinguish realism 'in ontology' (for objects), and 'in truth-value' (for being either true or false) [Shapiro]
     Full Idea: We must distinguish between 'realism in ontology' - that mathematical objects exist - and 'realism in truth-value', which is suggested by the model-theoretic framework - that each well-formed meaningful sentence is non-vacuously either true or false.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], Intro)
     A reaction: My inclination is fairly strongly towards realism of the second kind, but not of the first. A view about the notion of a 'truth-maker' might therefore be required. What do the truths refer to? Answer: not objects, but abstractions from objects.
If mathematical objects are accepted, then a number of standard principles will follow [Shapiro]
     Full Idea: One who believes in the independent existence of mathematical objects is likely to accept the law of excluded middle, impredicative definitions, the axiom of choice, extensionality, and arbitrary sets and functions.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 1)
     A reaction: The underlying thought is that since the objects pre-exist, all of the above simply describe the relations between them, rather than having to actually bring the objects into existence. Personally I would seek a middle ground.
Platonists claim we can state the essence of a number without reference to the others [Shapiro]
     Full Idea: The Platonist view may be that one can state the essence of each number, without referring to the other numbers.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 3.1)
     A reaction: Frege certainly talks this way (in his 'borehole' analogy). Fine, we are asked to spell out the essence of some number, without making reference either to any 'units' composing it, or to any other number adjacent to it or composing it. Reals?
Platonism must accept that the Peano Axioms could all be false [Shapiro]
     Full Idea: A traditional Platonist has to face the possibility that all of the Peano Axioms are false.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 4.7)
     A reaction: This would be because the objects exist independently, and so the Axioms are a mere human attempt at pinning them down. For the Formalist the axioms create the numbers, and so couldn't be false. This makes me, alas, warm to platonism!
6. Mathematics / C. Sources of Mathematics / 2. Intuition of Mathematics
Intuition is an outright hindrance to five-dimensional geometry [Shapiro]
     Full Idea: Even if spatial intuition provides a little help in the heuristics of four-dimensional geometry, intuition is an outright hindrance for five-dimensional geometry and beyond.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 5.2)
     A reaction: One might respond by saying 'so much the worse for five-dimensional geometry'. One could hardly abolish the subject, though, so the point must be taken.
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
A stone is a position in some pattern, and can be viewed as an object, or as a location [Shapiro]
     Full Idea: For each stone, there is at least one pattern such that the stone is a position in that pattern. The stone can be treated in terms of places-are-objects, or places-are-offices, to be filled with objects drawn from another ontology.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 8.4)
     A reaction: I believe this is the story J.S. Mill had in mind. His view was that the structures move off into abstraction, but it is only at the empirical and physical level that we can possibly learn the structures.
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
Can the ideal constructor also destroy objects? [Shapiro]
     Full Idea: Can we assume that the ideal constructor cannot destroy objects? Presumably the ideal constructor does not have an eraser, and the collection of objects is non-reducing over time.
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 6.5)
     A reaction: A very nice question, which platonists should enjoy.
Presumably nothing can block a possible dynamic operation? [Shapiro]
     Full Idea: Presumably within a dynamic system, once the constructor has an operation available, then no activity can preclude the performance of the operation?
     From: Stewart Shapiro (Philosophy of Mathematics [1997], 6.5)
     A reaction: There seems to be an interesting assumption in static accounts of mathematics, that all the possible outputs of (say) a function actually exist with a theory. In an actual dynamic account, the constructor may be smitten with lethargy.