Combining Texts

All the ideas for 'The Elements of Law', 'Justice as fairness: Political not Metaphysical' and 'Higher-Order Logic'

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22 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / b. Seventeenth century philosophy
7396 Hobbes created English-language philosophy [Hobbes, by Tuck]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
10301 The axiom of choice is controversial, but it could be replaced [Shapiro]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
10588 First-order logic is Complete, and Compact, with the Löwenheim-Skolem Theorems [Shapiro]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
10298 Some say that second-order logic is mathematics, not logic [Shapiro]
10299 If the aim of logic is to codify inferences, second-order logic is useless [Shapiro]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
10300 Logical consequence can be defined in terms of the logical terminology [Shapiro]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
10290 Second-order variables also range over properties, sets, relations or functions [Shapiro]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
10590 Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
10296 The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [Shapiro]
10297 The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
10292 Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / e. Peano arithmetic 2nd-order
10294 Second-order logic has the expressive power for mathematics, but an unworkable model theory [Shapiro]
8. Modes of Existence / B. Properties / 11. Properties as Sets
10591 Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
16638 The qualities of the world are mere appearances; reality is the motions which cause them [Hobbes]
12. Knowledge Sources / D. Empiricism / 1. Empiricism
16688 Evidence is conception, which is imagination, which proceeds from the senses [Hobbes]
7405 Experience can't prove universal truths [Hobbes]
20. Action / C. Motives for Action / 1. Acting on Desires
7408 It is an error that reason should control the passions, which give right guidance on their own [Hobbes, by Tuck]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
7407 Good and evil are what please us; goodness and badness the powers causing them [Hobbes]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
7410 Self-preservation is basic, and people judge differently about that, implying ethical relativism [Hobbes, by Tuck]
22. Metaethics / C. The Good / 1. Goodness / c. Right and good
7409 Hobbes shifted from talk of 'the good' to talk of 'rights' [Hobbes, by Tuck]
23. Ethics / E. Utilitarianism / 4. Unfairness
22406 The maximisation of happiness must be done fairly [Rawls, by Smart]
28. God / C. Attitudes to God / 4. God Reflects Humanity
7411 The attributes of God just show our inability to conceive his nature [Hobbes]