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All the ideas for 'Tusculan Disputations', 'The Question of Ontology' and 'Higher-Order Logic'

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31 ideas

1. Philosophy / A. Wisdom / 2. Wise People
5893 A wise man has integrity, firmness of will, nobility, consistency, sobriety, patience [Cicero]
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / e. Philosophy as reason
5891 Philosophy is the collection of rational arguments [Cicero]
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]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
12215 The existence of numbers is not a matter of identities, but of constituents of the world [Fine,K]
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
12211 It is plausible that x^2 = -1 had no solutions before complex numbers were 'introduced' [Fine,K]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
12209 The indispensability argument shows that nature is non-numerical, not the denial of numbers [Fine,K]
7. Existence / A. Nature of Existence / 1. Nature of Existence
12214 'Exists' is a predicate, not a quantifier; 'electrons exist' is like 'electrons spin' [Fine,K]
7. Existence / A. Nature of Existence / 4. Abstract Existence
12212 Just as we introduced complex numbers, so we introduced sums and temporal parts [Fine,K]
7. Existence / A. Nature of Existence / 6. Criterion for Existence
12216 Real objects are those which figure in the facts that constitute reality [Fine,K]
12218 Being real and being fundamental are separate; Thales's water might be real and divisible [Fine,K]
7. Existence / D. Theories of Reality / 1. Ontologies
12217 For ontology we need, not internal or external views, but a view from outside reality [Fine,K]
7. Existence / D. Theories of Reality / 11. Ontological Commitment / b. Commitment of quantifiers
12213 Ontological claims are often universal, and not a matter of existential quantification [Fine,K]
8. Modes of Existence / B. Properties / 11. Properties as Sets
10591 Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
15. Nature of Minds / A. Nature of Mind / 2. Psuche
5879 The soul is the heart, or blood in the heart, or part of the brain, of something living in heart or brain, or breath [Cicero]
15. Nature of Minds / A. Nature of Mind / 5. Unity of Mind
5884 How can one mind perceive so many dissimilar sensations? [Cicero]
5887 The soul has a single nature, so it cannot be divided, and hence it cannot perish [Cicero]
16. Persons / C. Self-Awareness / 3. Limits of Introspection
5886 Like the eye, the soul has no power to see itself, but sees other things [Cicero]
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / a. Physicalism critique
5885 Souls contain no properties of elements, and elements contain no properties of souls [Cicero]
23. Ethics / C. Virtue Theory / 3. Virtues / f. Compassion
5890 We should not share the distress of others, but simply try to relieve it [Cicero]
23. Ethics / C. Virtue Theory / 4. External Goods / c. Wealth
5894 All men except philosophers fear poverty [Cicero]
24. Political Theory / D. Ideologies / 5. Democracy / f. Against democracy
5895 If one despises illiterate mechanics individually, they are not worth more collectively [Cicero]