Combining Texts

All the ideas for 'works (all lost)', 'Higher-Order Logic' and 'The Basing Relation'

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20 ideas

1. Philosophy / D. Nature of Philosophy / 6. Hopes for Philosophy
If all laws were abolished, philosophers would still live as they do now [Aristippus elder]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
The axiom of choice is controversial, but it could be replaced [Shapiro]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
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
Some say that second-order logic is mathematics, not logic [Shapiro]
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
Logical consequence can be defined in terms of the logical terminology [Shapiro]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
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
The Löwenheim-Skolem theorem seems to be a defect of first-order logic [Shapiro]
Up Löwenheim-Skolem: if natural numbers satisfy wffs, then an infinite domain satisfies them [Shapiro]
Downward Löwenheim-Skolem: if there's an infinite model, there is a countable model [Shapiro]
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
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
Logicians use 'property' and 'set' interchangeably, with little hanging on it [Shapiro]
11. Knowledge Aims / A. Knowledge / 4. Belief / a. Beliefs
There are reasons 'for which' a belief is held, reasons 'why' it is believed, and reasons 'to' believe it [Neta]
The basing relation of a reason to a belief should both support and explain the belief [Neta]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / h. Against ethics
Only the Cyrenaics reject the idea of a final moral end [Aristippus elder, by Annas]
22. Metaethics / C. The Good / 2. Happiness / d. Routes to happiness
The road of freedom is the surest route to happiness [Aristippus elder, by Xenophon]
23. Ethics / A. Egoism / 3. Cyrenaic School
Pleasure is the good, because we always seek it, it satisfies us, and its opposite is the most avoidable thing [Aristippus elder, by Diog. Laertius]
People who object to extravagant pleasures just love money [Aristippus elder, by Diog. Laertius]
25. Social Practice / D. Justice / 3. Punishment / b. Retribution for crime
Errors result from external influence, and should be corrected, not hated [Aristippus elder, by Diog. Laertius]