Combining Texts

All the ideas for 'Purifications (frags)', 'What are Sets and What are they For?' and 'Supervenience'

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18 ideas

4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
14239 The empty set is usually derived from Separation, but it also seems to need Infinity [Oliver/Smiley]
14240 The empty set is something, not nothing! [Oliver/Smiley]
14241 We don't need the empty set to express non-existence, as there are other ways to do that [Oliver/Smiley]
14242 Maybe we can treat the empty set symbol as just meaning an empty term [Oliver/Smiley]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
14243 The unit set may be needed to express intersections that leave a single member [Oliver/Smiley]
5. Theory of Logic / G. Quantification / 6. Plural Quantification
14234 If you only refer to objects one at a time, you need sets in order to refer to a plurality [Oliver/Smiley]
14237 We can use plural language to refer to the set theory domain, to avoid calling it a 'set' [Oliver/Smiley]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
14245 Logical truths are true no matter what exists - but predicate calculus insists that something exists [Oliver/Smiley]
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / g. Applying mathematics
14246 If mathematics purely concerned mathematical objects, there would be no applied mathematics [Oliver/Smiley]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
14247 Sets might either represent the numbers, or be the numbers, or replace the numbers [Oliver/Smiley]
7. Existence / C. Structure of Existence / 5. Supervenience / a. Nature of supervenience
16039 Supervenience: No A-difference without a B-difference [Bennett,K]
16043 Supervenience is non-symmetric - sometimes it's symmetric, and sometimes it's one-way [Bennett,K]
7. Existence / C. Structure of Existence / 5. Supervenience / b. Types of supervenience
16047 Weak supervenience is in one world, strong supervenience in all possible worlds [Bennett,K]
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
16040 Aesthetics, morality and mind supervene on the physical? Modal on non-modal? General on particular? [Bennett,K]
16044 Some entailments do not involve supervenience, as when brotherhood entails siblinghood [Bennett,K]
16046 Reduction requires supervenience, but does supervenience suffice for reduction? [Bennett,K]
7. Existence / D. Theories of Reality / 6. Physicalism
16049 Definitions of physicalism are compatible with a necessary God [Bennett,K]
10. Modality / A. Necessity / 6. Logical Necessity
16042 The metaphysically and logically possible worlds are the same, so they are the same strength [Bennett,K]