Combining Texts

All the ideas for 'The Logic of Boundaryless Concepts', 'The Case against Closure (and reply)' and 'Philosophy of Logic'

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34 ideas

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]
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]
Logic guides thinking, but it isn't a substitute for it [Rumfitt]
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]
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 / B. Unity of Objects / 3. Unity Problems / e. Vague objects
Vague membership of sets is possible if the set is defined by its concept, not its members [Rumfitt]
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 / A. Justification Problems / 2. Justification Challenges / c. Knowledge closure
Closure says if you know P, and also know P implies Q, then you must know Q [Dretske]
We needn't regret the implications of our regrets; regretting drinking too much implies the past is real [Dretske]
Reasons for believing P may not transmit to its implication, Q [Dretske]
Knowing by visual perception is not the same as knowing by implication [Dretske]
The only way to preserve our homely truths is to abandon closure [Dretske]
P may imply Q, but evidence for P doesn't imply evidence for Q, so closure fails [Dretske]
We know past events by memory, but we don't know the past is real (an implication) by memory [Dretske]
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]