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All the ideas for '', 'What are Sets and What are they For?' and 'Straw Dogs'

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21 ideas

1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
9271 Human knowledge may not produce well-being; the examined life may not be worth living [Gray]
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 / A. Overview of Logic / 1. Overview of Logic
11211 If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt]
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
11210 Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt]
11212 The sense of a connective comes from primitively obvious rules of inference [Rumfitt]
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]
13. Knowledge Criteria / C. External Justification / 9. Naturalised Epistemology
9275 Knowledge does not need minds or nervous systems; it is found in all living things [Gray]
16. Persons / F. Free Will / 5. Against Free Will
9276 The will hardly ever does anything; most of our life just happens to us [Gray]
19. Language / F. Communication / 3. Denial
11214 We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt]
25. Social Practice / A. Freedoms / 5. Freedom of lifestyle
9278 Nowadays we identify the free life with the good life [Gray]
27. Natural Reality / G. Biology / 4. Ecology
9280 Over forty percent of the Earth's living tissue is human [Gray]
29. Religion / B. Monotheistic Religion / 4. Christianity / a. Christianity
9272 Without Christianity we lose the idea that human history has a meaning [Gray]
9279 What was our original sin, and how could Christ's suffering redeem it? [Gray]