Combining Texts

All the ideas for 'Time Without Change', 'Philosophy of Logic' and 'Elements of Mathematical Logic'

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33 ideas

2. Reason / A. Nature of Reason / 9. Limits of Reason
People have had good reasons for thinking that the circle has been squared [Shoemaker]
2. Reason / B. Laws of Thought / 3. Non-Contradiction
If you say that a contradiction is true, you change the meaning of 'not', and so change the subject [Quine]
3. Truth / F. Semantic Truth / 2. Semantic Truth
Talk of 'truth' when sentences are mentioned; it reminds us that reality is the point of sentences [Quine]
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth is redundant for single sentences; we do better to simply speak the sentence [Quine]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
We can eliminate 'or' from our basic theory, by paraphrasing 'p or q' as 'not(not-p and not-q)' [Quine]
4. Formal Logic / E. Nonclassical Logics / 3. Many-Valued Logic
Lukasiewicz's L3 logic has three truth-values, T, F and I (for 'indeterminate') [Lukasiewicz, by Fisher]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
My logical grammar has sentences by predication, then negation, conjunction, and existential quantification [Quine]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Maybe logical truth reflects reality, but in different ways in different languages [Quine]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Quine rejects second-order logic, saying that predicates refer to multiple objects [Quine, by Hodes]
Quantifying over predicates is treating them as names of entities [Quine]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle has three different definitions [Quine]
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Quantification theory can still be proved complete if we add identity [Quine]
5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
Names are not essential, because naming can be turned into predication [Quine]
5. Theory of Logic / G. Quantification / 1. Quantification
Universal quantification is widespread, but it is definable in terms of existential quantification [Quine]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
You can't base quantification on substituting names for variables, if the irrationals cannot all be named [Quine]
Some quantifications could be false substitutionally and true objectually, because of nameless objects [Quine]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Putting a predicate letter in a quantifier is to make it the name of an entity [Quine]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A sentence is logically true if all sentences with that grammatical structure are true [Quine]
7. Existence / D. Theories of Reality / 4. Anti-realism
Inability to measure equality doesn't make all lengths unequal [Shoemaker]
We couldn't verify the earth's rotation if everyone simultaneously fell asleep [Shoemaker]
8. Modes of Existence / B. Properties / 12. Denial of Properties
Predicates are not names; predicates are the other parties to predication [Quine]
9. Objects / A. Existence of Objects / 1. Physical Objects
A physical object is the four-dimensional material content of a portion of space-time [Quine]
9. Objects / E. Objects over Time / 4. Four-Dimensionalism
Four-d objects helps predication of what no longer exists, and quantification over items from different times [Quine]
10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional
Some conditionals can be explained just by negation and conjunction: not(p and not-q) [Quine]
13. Knowledge Criteria / D. Scepticism / 1. Scepticism
Maybe billions of changeless years have elapsed since my last meal [Shoemaker]
19. Language / A. Nature of Meaning / 8. Synonymy
Single words are strongly synonymous if their interchange preserves truth [Quine]
19. Language / D. Propositions / 6. Propositions Critique
It makes no sense to say that two sentences express the same proposition [Quine]
There is no rule for separating the information from other features of sentences [Quine]
We can abandon propositions, and just talk of sentences and equivalence [Quine]
19. Language / F. Communication / 5. Pragmatics / a. Contextual meaning
A good way of explaining an expression is saying what conditions make its contexts true [Quine]
26. Natural Theory / C. Causation / 9. General Causation / a. Constant conjunction
If things turn red for an hour and then explode, we wouldn't say the redness was the cause [Shoemaker]
27. Natural Reality / D. Time / 1. Nature of Time / e. Eventless time
If three regions 'freeze' every three, four and five years, after sixty years everything stops for a year [Shoemaker, by Lowe]
If three regions freeze every 3rd, 4th and 5th year, they all freeze together every 60 years [Shoemaker]