64 ideas
3099 | Inference is never a conscious process [Harman] |
3077 | Reasoning might be defined in terms of its functional role, which is to produce knowledge [Harman] |
3092 | If you believe that some of your beliefs are false, then at least one of your beliefs IS false [Harman] |
17774 | Definitions make our intuitions mathematically useful [Mayberry] |
17773 | Proof shows that it is true, but also why it must be true [Mayberry] |
17795 | Set theory can't be axiomatic, because it is needed to express the very notion of axiomatisation [Mayberry] |
17796 | There is a semi-categorical axiomatisation of set-theory [Mayberry] |
17800 | The misnamed Axiom of Infinity says the natural numbers are finite in size [Mayberry] |
17801 | The set hierarchy doesn't rely on the dubious notion of 'generating' them [Mayberry] |
17803 | Limitation of size is part of the very conception of a set [Mayberry] |
3093 | Any two states are logically linked, by being entailed by their conjunction [Harman] |
17786 | The mainstream of modern logic sees it as a branch of mathematics [Mayberry] |
17788 | First-order logic only has its main theorems because it is so weak [Mayberry] |
3098 | Deductive logic is the only logic there is [Harman] |
17791 | Only second-order logic can capture mathematical structure up to isomorphism [Mayberry] |
3094 | You don't have to accept the conclusion of a valid argument [Harman] |
3084 | Our underlying predicates represent words in the language, not universal concepts [Harman] |
3080 | Logical form is the part of a sentence structure which involves logical elements [Harman] |
3081 | A theory of truth in a language must involve a theory of logical form [Harman] |
17787 | Big logic has one fixed domain, but standard logic has a domain for each interpretation [Mayberry] |
17790 | No Löwenheim-Skolem logic can axiomatise real analysis [Mayberry] |
17779 | 'Classificatory' axioms aim at revealing similarity in morphology of structures [Mayberry] |
17778 | Axiomatiation relies on isomorphic structures being essentially the same [Mayberry] |
17780 | 'Eliminatory' axioms get rid of traditional ideal and abstract objects [Mayberry] |
17789 | No logic which can axiomatise arithmetic can be compact or complete [Mayberry] |
17784 | Real numbers can be eliminated, by axiom systems for complete ordered fields [Mayberry] |
17782 | Greek quantities were concrete, and ratio and proportion were their science [Mayberry] |
17781 | Real numbers were invented, as objects, to simplify and generalise 'quantity' [Mayberry] |
17799 | Cantor's infinite is an absolute, of all the sets or all the ordinal numbers [Mayberry] |
17797 | Cantor extended the finite (rather than 'taming the infinite') [Mayberry] |
17775 | If proof and definition are central, then mathematics needs and possesses foundations [Mayberry] |
17776 | The ultimate principles and concepts of mathematics are presumed, or grasped directly [Mayberry] |
17777 | Foundations need concepts, definition rules, premises, and proof rules [Mayberry] |
17804 | Axiom theories can't give foundations for mathematics - that's using axioms to explain axioms [Mayberry] |
17792 | 1st-order PA is only interesting because of results which use 2nd-order PA [Mayberry] |
17793 | It is only 2nd-order isomorphism which suggested first-order PA completeness [Mayberry] |
17794 | Set theory is not just first-order ZF, because that is inadequate for mathematics [Mayberry] |
17802 | We don't translate mathematics into set theory, because it comes embodied in that way [Mayberry] |
17805 | Set theory is not just another axiomatised part of mathematics [Mayberry] |
10580 | Mathematics is both necessary and a priori because it really consists of logical truths [Yablo] |
10579 | Putting numbers in quantifiable position (rather than many quantifiers) makes expression easier [Yablo] |
10577 | Concrete objects have few essential properties, but properties of abstractions are mostly essential [Yablo] |
10578 | We are thought to know concreta a posteriori, and many abstracta a priori [Yablo] |
17785 | Real numbers as abstracted objects are now treated as complete ordered fields [Mayberry] |
3100 | You have to reaffirm all your beliefs when you make a logical inference [Harman] |
3089 | Only lack of imagination makes us think that 'cats are animals' is analytic [Harman] |
3088 | Analyticity is postulated because we can't imagine some things being true, but we may just lack imagination [Harman] |
3101 | Memories are not just preserved, they are constantly reinferred [Harman] |
3074 | People's reasons for belief are rarely conscious [Harman] |
3097 | We don't distinguish between accepting, and accepting as evidence [Harman] |
6369 | In negative coherence theories, beliefs are prima facie justified, and don't need initial reasons [Harman, by Pollock/Cruz] |
3096 | Coherence avoids scepticism, because it doesn't rely on unprovable foundations [Harman] |
3095 | Induction is an attempt to increase the coherence of our explanations [Harman] |
3073 | We see ourselves in the world as a map [Harman] |
3076 | Defining dispositions is circular [Harman] |
3075 | Could a cloud have a headache if its particles formed into the right pattern? [Harman] |
3086 | Are there any meanings apart from in a language? [Harman] |
3078 | Speech acts, communication, representation and truth form a single theory [Harman] |
3090 | There is only similarity in meaning, never sameness in meaning [Harman] |
3082 | Ambiguity is when different underlying truth-conditional structures have the same surface form [Harman] |
3079 | Truth in a language is explained by how the structural elements of a sentence contribute to its truth conditions [Harman] |
3085 | Sentences are different from propositions, since two sentences can express one proposition [Harman] |
3087 | The analytic/synthetic distinction is a silly division of thought into encyclopaedia and dictionary [Harman] |
3083 | Many predicates totally resist translation, so a universal underlying structure to languages is unlikely [Harman] |