35 ideas
9023 | If you say that a contradiction is true, you change the meaning of 'not', and so change the subject [Quine] |
10153 | In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski] |
9012 | Talk of 'truth' when sentences are mentioned; it reminds us that reality is the point of sentences [Quine] |
19141 | Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson] |
9011 | Truth is redundant for single sentences; we do better to simply speak the sentence [Quine] |
9013 | We can eliminate 'or' from our basic theory, by paraphrasing 'p or q' as 'not(not-p and not-q)' [Quine] |
9020 | My logical grammar has sentences by predication, then negation, conjunction, and existential quantification [Quine] |
11211 | If a sound conclusion comes from two errors that cancel out, the path of the argument must matter [Rumfitt] |
9028 | Maybe logical truth reflects reality, but in different ways in different languages [Quine] |
10048 | There is no clear boundary between the logical and the non-logical [Tarski] |
10014 | Quine rejects second-order logic, saying that predicates refer to multiple objects [Quine, by Hodes] |
10828 | Quantifying over predicates is treating them as names of entities [Quine] |
10694 | Logical consequence is when in any model in which the premises are true, the conclusion is true [Tarski, by Beall/Restall] |
10479 | Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W] |
9024 | Excluded middle has three different definitions [Quine] |
10012 | Quantification theory can still be proved complete if we add identity [Quine] |
11210 | Standardly 'and' and 'but' are held to have the same sense by having the same truth table [Rumfitt] |
11212 | The sense of a connective comes from primitively obvious rules of inference [Rumfitt] |
9016 | Names are not essential, because naming can be turned into predication [Quine] |
9015 | Universal quantification is widespread, but it is definable in terms of existential quantification [Quine] |
9025 | You can't base quantification on substituting names for variables, if the irrationals cannot all be named [Quine] |
9026 | Some quantifications could be false substitutionally and true objectually, because of nameless objects [Quine] |
10705 | Putting a predicate letter in a quantifier is to make it the name of an entity [Quine] |
9027 | A sentence is logically true if all sentences with that grammatical structure are true [Quine] |
10157 | Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman] |
9017 | Predicates are not names; predicates are the other parties to predication [Quine] |
9018 | A physical object is the four-dimensional material content of a portion of space-time [Quine] |
9019 | Four-d objects helps predication of what no longer exists, and quantification over items from different times [Quine] |
9014 | Some conditionals can be explained just by negation and conjunction: not(p and not-q) [Quine] |
9009 | Single words are strongly synonymous if their interchange preserves truth [Quine] |
9007 | It makes no sense to say that two sentences express the same proposition [Quine] |
9008 | There is no rule for separating the information from other features of sentences [Quine] |
9010 | We can abandon propositions, and just talk of sentences and equivalence [Quine] |
11214 | We learn 'not' along with affirmation, by learning to either affirm or deny a sentence [Rumfitt] |
9021 | A good way of explaining an expression is saying what conditions make its contexts true [Quine] |