58 ideas
6420 | Only by analysing is progress possible in philosophy [Russell] |
6432 | Analysis gives new knowledge, without destroying what we already have [Russell] |
6437 | The theory of types makes 'Socrates and killing are two' illegitimate [Russell] |
6442 | Truth belongs to beliefs, not to propositions and sentences [Russell] |
18194 | 'Forcing' can produce new models of ZFC from old models [Maddy] |
18195 | A Large Cardinal Axiom would assert ever-increasing stages in the hierarchy [Maddy] |
18191 | Axiom of Infinity: completed infinite collections can be treated mathematically [Maddy] |
18193 | The Axiom of Foundation says every set exists at a level in the set hierarchy [Maddy] |
18169 | Axiom of Reducibility: propositional functions are extensionally predicative [Maddy] |
6436 | I gradually replaced classes with properties, and they ended as a symbolic convenience [Russell] |
18739 | Three stages of philosophical logic: syntactic (1905-55), possible worlds (1963-85), widening (1990-) [Horsten/Pettigrew] |
7528 | Leibniz bases everything on subject/predicate and substance/property propositions [Russell] |
18168 | 'Propositional functions' are propositions with a variable as subject or predicate [Maddy] |
18741 | Logical formalization makes concepts precise, and also shows their interrelation [Horsten/Pettigrew] |
6439 | Names are meaningless unless there is an object which they designate [Russell] |
18744 | Models are sets with functions and relations, and truth built up from the components [Horsten/Pettigrew] |
18190 | Completed infinities resulted from giving foundations to calculus [Maddy] |
18171 | Cantor and Dedekind brought completed infinities into mathematics [Maddy] |
18172 | Infinity has degrees, and large cardinals are the heart of set theory [Maddy] |
18175 | For any cardinal there is always a larger one (so there is no set of all sets) [Maddy] |
18196 | An 'inaccessible' cardinal cannot be reached by union sets or power sets [Maddy] |
18187 | Theorems about limits could only be proved once the real numbers were understood [Maddy] |
18182 | The extension of concepts is not important to me [Maddy] |
18177 | In the ZFC hierarchy it is impossible to form Frege's set of all three-element sets [Maddy] |
18164 | Frege solves the Caesar problem by explicitly defining each number [Maddy] |
18184 | Making set theory foundational to mathematics leads to very fruitful axioms [Maddy] |
18185 | Unified set theory gives a final court of appeal for mathematics [Maddy] |
18183 | Set theory brings mathematics into one arena, where interrelations become clearer [Maddy] |
18186 | Identifying geometric points with real numbers revealed the power of set theory [Maddy] |
18188 | The line of rationals has gaps, but set theory provided an ordered continuum [Maddy] |
18163 | Mathematics rests on the logic of proofs, and on the set theoretic axioms [Maddy] |
18207 | Maybe applications of continuum mathematics are all idealisations [Maddy] |
18204 | Scientists posit as few entities as possible, but set theorist posit as many as possible [Maddy] |
6423 | We tried to define all of pure maths using logical premisses and concepts [Russell] |
18167 | We can get arithmetic directly from HP; Law V was used to get HP from the definition of number [Maddy] |
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] |
18740 | If 'exist' doesn't express a property, we can hardly ask for its essence [Horsten/Pettigrew] |
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] |
18205 | The theoretical indispensability of atoms did not at first convince scientists that they were real [Maddy] |
6440 | Universals can't just be words, because words themselves are universals [Russell] |
18745 | A Tarskian model can be seen as a possible state of affairs [Horsten/Pettigrew] |
18747 | The 'spheres model' was added to possible worlds, to cope with counterfactuals [Horsten/Pettigrew] |
18748 | Epistemic logic introduced impossible worlds [Horsten/Pettigrew] |
18746 | Possible worlds models contain sets of possible worlds; this is a large metaphysical commitment [Horsten/Pettigrew] |
18750 | Using possible worlds for knowledge and morality may be a step too far [Horsten/Pettigrew] |
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] |
18206 | Science idealises the earth's surface, the oceans, continuities, and liquids [Maddy] |
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] |
6435 | You can believe the meaning of a sentence without thinking of the words [Russell] |