Combining Texts

All the ideas for 'fragments/reports', 'Inquiry Concerning Virtue or Merit' and 'Higher-Order Logic'

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


21 ideas

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]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / c. Ethical intuitionism
Fear of God is not conscience, which is a natural feeling of offence at bad behaviour [Shaftesbury]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / h. Expressivism
If an irrational creature with kind feelings was suddenly given reason, its reason would approve of kind feelings [Shaftesbury]
22. Metaethics / C. The Good / 1. Goodness / g. Consequentialism
A person isn't good if only tying their hands prevents their mischief, so the affections decide a person's morality [Shaftesbury]
22. Metaethics / C. The Good / 3. Pleasure / d. Sources of pleasure
People more obviously enjoy social pleasures than they do eating and drinking [Shaftesbury]
23. Ethics / A. Egoism / 1. Ethical Egoism
Self-interest is not intrinsically good, but its absence is evil, as public good needs it [Shaftesbury]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / b. Basis of virtue
Every creature has a right and a wrong state which guide its actions, so there must be a natural end [Shaftesbury]
25. Social Practice / E. Policies / 5. Education / b. Education principles
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
Time is an interval of motion, or the measure of speed [Posidonius, by Stobaeus]
28. God / A. Divine Nature / 6. Divine Morality / b. Euthyphro question
For Shaftesbury, we must already have a conscience to be motivated to religious obedience [Shaftesbury, by Scruton]