Combining Texts

All the ideas for 'Fragments of Democritus', 'On Eternal and Immutable Morality' and 'Higher-Order Logic'

expand these ideas     |    start again     |     specify just one area for these texts

20 ideas

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 / A. A Priori Knowledge / 3. Innate Knowledge / c. Tabula rasa
6230 If the soul were a tabula rasa, with no innate ideas, there could be no moral goodness or justice [Cudworth]
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
6228 Senses cannot judge one another, so what judges senses cannot be a sense, but must be superior [Cudworth]
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / a. Physicalism critique
6229 Sense is fixed in the material form, and so can't grasp abstract universals [Cudworth]
22. Metaethics / B. Value / 1. Nature of Value / c. Objective value
6227 Keeping promises and contracts is an obligation of natural justice [Cudworth]
25. Social Practice / D. Justice / 2. The Law / c. Natural law
6225 Obligation to obey all positive laws is older than all laws [Cudworth]
28. God / A. Divine Nature / 4. Divine Contradictions
6224 An omnipotent will cannot make two things equal or alike if they aren't [Cudworth]
28. God / A. Divine Nature / 6. Divine Morality / d. God decrees morality
6223 If the will and pleasure of God controls justice, then anything wicked or unjust would become good if God commanded it [Cudworth]
6226 The requirement that God must be obeyed must precede any authority of God's commands [Cudworth]