Combining Texts

All the ideas for 'fragments/reports', 'Higher-Order Logic' and 'The Journals of Kierkegaard'

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21 ideas

1. Philosophy / D. Nature of Philosophy / 2. Invocation to Philosophy
16000 Fixed ideas should be tackled aggressively [Kierkegaard]
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
16012 Philosophy can't be unbiased if it ignores language, as that is no more independent than individuals are [Kierkegaard]
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
10297 The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
10590 Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
10292 Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
10296 The Löwenheim-Skolem Theorems fail for second-order languages with standard semantics [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]
22. Metaethics / B. Value / 2. Values / g. Love
16003 If people marry just because they are lonely, that is self-love, not love [Kierkegaard]
23. Ethics / F. Existentialism / 4. Boredom
21910 Our destiny is the highest pitch of world-weariness [Kierkegaard]
23. Ethics / F. Existentialism / 7. Existential Action
16001 Life may be understood backwards, but it has to be lived forwards [Kierkegaard]
25. Social Practice / E. Policies / 5. Education / b. Education principles
13304 Learned men gain more in one day than others do in a lifetime [Posidonius]
27. Natural Reality / D. Time / 1. Nature of Time / d. Time as measure
20820 Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]
29. Religion / B. Monotheistic Religion / 4. Christianity / a. Christianity
16008 The best way to be a Christian is without 'Christianity' [Kierkegaard]
20735 We need to see that Christianity cannot be understood [Kierkegaard]