61 ideas
| 6420 | Only by analysing is progress possible in philosophy [Russell] |
| 6432 | Analysis gives new knowledge, without destroying what we already have [Russell] |
| 9023 | If you say that a contradiction is true, you change the meaning of 'not', and so change the subject [Quine] |
| 6437 | The theory of types makes 'Socrates and killing are two' illegitimate [Russell] |
| 6442 | Truth belongs to beliefs, not to propositions and sentences [Russell] |
| 9012 | Talk of 'truth' when sentences are mentioned; it reminds us that reality is the point of sentences [Quine] |
| 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] |
| 6436 | I gradually replaced classes with properties, and they ended as a symbolic convenience [Russell] |
| 9020 | My logical grammar has sentences by predication, then negation, conjunction, and existential quantification [Quine] |
| 9028 | Maybe logical truth reflects reality, but in different ways in different languages [Quine] |
| 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] |
| 9024 | Excluded middle has three different definitions [Quine] |
| 10012 | Quantification theory can still be proved complete if we add identity [Quine] |
| 7528 | Leibniz bases everything on subject/predicate and substance/property propositions [Russell] |
| 6439 | Names are meaningless unless there is an object which they designate [Russell] |
| 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] |
| 6423 | We tried to define all of pure maths using logical premisses and concepts [Russell] |
| 6424 | Formalists say maths is merely conventional marks on paper, like the arbitrary rules of chess [Russell] |
| 6425 | Formalism can't apply numbers to reality, so it is an evasion [Russell] |
| 6426 | Intuitionism says propositions are only true or false if there is a method of showing it [Russell] |
| 6419 | In 1899-1900 I adopted the philosophy of logical atomism [Russell] |
| 6438 | Complex things can be known, but not simple things [Russell] |
| 6434 | Facts are everything, except simples; they are either relations or qualities [Russell] |
| 9017 | Predicates are not names; predicates are the other parties to predication [Quine] |
| 6440 | Universals can't just be words, because words themselves are universals [Russell] |
| 9018 | A physical object is the four-dimensional material content of a portion of space-time [Quine] |
| 12132 | Indiscernibility is a necessary and sufficient condition for identity [Brody] |
| 15834 | Brody bases sortal essentialism on properties required throughout something's existence [Brody, by Mackie,P] |
| 12140 | Modern emphasis is on properties had essentially; traditional emphasis is on sort-defining properties [Brody] |
| 11895 | A sortal essence is a property which once possessed always possessed [Brody, by Mackie,P] |
| 12141 | Maybe essential properties are those which determine a natural kind? [Brody] |
| 12137 | De re essentialism standardly says all possible objects identical with a have a's essential properties [Brody] |
| 12142 | Essentially, a has P, always had P, must have had P, and has never had a future without P [Brody] |
| 12143 | An object having a property essentially is equivalent to its having it necessarily [Brody] |
| 12144 | Essentialism is justified if the essential properties of things explain their other properties [Brody] |
| 12139 | Mereological essentialism says that every part that ensures the existence is essential [Brody] |
| 9019 | Four-d objects helps predication of what no longer exists, and quantification over items from different times [Quine] |
| 12135 | Interrupted objects have two first moments of existence, which could be two beginnings [Brody] |
| 12130 | a and b share all properties; so they share being-identical-with-a; so a = b [Brody] |
| 9014 | Some conditionals can be explained just by negation and conjunction: not(p and not-q) [Quine] |
| 12138 | Identity across possible worlds is prior to rigid designation [Brody] |
| 6430 | In epistemology we should emphasis the continuity between animal and human minds [Russell] |
| 6441 | Pragmatism judges by effects, but I judge truth by causes [Russell] |
| 6431 | Empiricists seem unclear what they mean by 'experience' [Russell] |
| 6444 | True belief about the time is not knowledge if I luckily observe a stopped clock at the right moment [Russell] |
| 6433 | Behaviourists struggle to explain memory and imagination, because they won't admit images [Russell] |
| 6443 | Surprise is a criterion of error [Russell] |
| 6427 | Unverifiable propositions about the remote past are still either true or false [Russell] |
| 9009 | Single words are strongly synonymous if their interchange preserves truth [Quine] |
| 6435 | You can believe the meaning of a sentence without thinking of the words [Russell] |
| 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] |
| 9021 | A good way of explaining an expression is saying what conditions make its contexts true [Quine] |