Combining Texts

All the ideas for 'Must We Believe in Set Theory?st1=George Boolos', 'Concepts without Boundaries' and 'Against the Ethicists (one book)'

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19 ideas

2. Reason / A. Nature of Reason / 9. Limits of Reason
22752 Reasoning is impossible without a preconception [Sext.Empiricus]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
10482 The logic of ZF is classical first-order predicate logic with identity [Boolos]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / a. Axioms for sets
10492 A few axioms of set theory 'force themselves on us', but most of them don't [Boolos]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
10485 Naïve sets are inconsistent: there is no set for things that do not belong to themselves [Boolos]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
10484 The iterative conception says sets are formed at stages; some are 'earlier', and must be formed first [Boolos]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
10491 Infinite natural numbers is as obvious as infinite sentences in English [Boolos]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
10483 Mathematics and science do not require very high orders of infinity [Boolos]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / a. For mathematical platonism
10490 Mathematics isn't surprising, given that we experience many objects as abstract [Boolos]
7. Existence / D. Theories of Reality / 10. Vagueness / b. Vagueness of reality
8983 If 'red' is vague, then membership of the set of red things is vague, so there is no set of red things [Sainsbury]
7. Existence / E. Categories / 2. Categorisation
8986 We should abandon classifying by pigeon-holes, and classify around paradigms [Sainsbury]
8. Modes of Existence / D. Universals / 1. Universals
10488 It is lunacy to think we only see ink-marks, and not word-types [Boolos]
9. Objects / A. Existence of Objects / 2. Abstract Objects / a. Nature of abstracta
10487 I am a fan of abstract objects, and confident of their existence [Boolos]
9. Objects / A. Existence of Objects / 2. Abstract Objects / c. Modern abstracta
10489 We deal with abstract objects all the time: software, poems, mistakes, triangles.. [Boolos]
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
8982 Vague concepts are concepts without boundaries [Sainsbury]
8984 If concepts are vague, people avoid boundaries, can't spot them, and don't want them [Sainsbury]
8985 Boundaryless concepts tend to come in pairs, such as child/adult, hot/cold [Sainsbury]
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
22754 Saying the good is useful or choiceworth or happiness-creating is not the good, but a feature of it [Sext.Empiricus]
22. Metaethics / C. The Good / 1. Goodness / b. Types of good
22755 Like a warming fire, what is good by nature should be good for everyone [Sext.Empiricus]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
22756 If a desire is itself desirable, then we shouldn't desire it, as achieving it destroys it [Sext.Empiricus]