Combining Texts

All the ideas for 'Locke on Human Understanding', 'Higher-Order Logic' and 'works'

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21 ideas

2. Reason / B. Laws of Thought / 2. Sufficient Reason
Sufficient reason is implied by contradiction, of an insufficient possible which exists [Wolff, by Korsgaard]
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]
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
Two things can only resemble one another in some respect, and that may reintroduce a universal [Lowe]
9. Objects / B. Unity of Objects / 2. Substance / d. Substance defined
On substances, Leibniz emphasises unity, Spinoza independence, Locke relations to qualities [Lowe]
12. Knowledge Sources / B. Perception / 6. Inference in Perception
Perception is a mode of belief-acquisition, and does not involve sensation [Lowe]
12. Knowledge Sources / B. Perception / 7. Causal Perception
Science requires a causal theory - perception of an object must be an experience caused by the object [Lowe]
16. Persons / D. Continuity of the Self / 1. Identity and the Self
Personal identity is a problem across time (diachronic) and at an instant (synchronic) [Lowe]
18. Thought / B. Mechanics of Thought / 4. Language of Thought
Mentalese isn't a language, because it isn't conventional, or a means of public communication [Lowe]
19. Language / A. Nature of Meaning / 2. Meaning as Mental
If meaning is mental pictures, explain "the cat (or dog!) is NOT on the mat" [Lowe]
28. God / A. Divine Nature / 6. Divine Morality / b. Euthyphro question
Confucius shows that ethics can rest on reason, rather than on revelation [Wolff, by Korsgaard]