66 ideas
17729 | Examining concepts can recover information obtained through the senses [Jenkins] |
8721 | An 'impredicative' definition seems circular, because it uses the term being defined [Friend] |
8680 | Classical definitions attempt to refer, but intuitionist/constructivist definitions actually create objects [Friend] |
3678 | Reductio ad absurdum proves an idea by showing that its denial produces contradiction [Friend] |
3745 | Must sentences make statements to qualify for truth? [O'Connor] |
8705 | Anti-realists see truth as our servant, and epistemically contrained [Friend] |
3742 | Beliefs must match facts, but also words must match beliefs [O'Connor] |
17740 | Instead of correspondence of proposition to fact, look at correspondence of its parts [Jenkins] |
3744 | The semantic theory requires sentences as truth-bearers, not propositions [O'Connor] |
3749 | What does 'true in English' mean? [O'Connor] |
8713 | In classical/realist logic the connectives are defined by truth-tables [Friend] |
8708 | Double negation elimination is not valid in intuitionist logic [Friend] |
8694 | Free logic was developed for fictional or non-existent objects [Friend] |
8665 | A 'proper subset' of A contains only members of A, but not all of them [Friend] |
8672 | A 'powerset' is all the subsets of a set [Friend] |
8677 | Set theory makes a minimum ontological claim, that the empty set exists [Friend] |
8666 | Infinite sets correspond one-to-one with a subset [Friend] |
8682 | Major set theories differ in their axioms, and also over the additional axioms of choice and infinity [Friend] |
3746 | Logic seems to work for unasserted sentences [O'Connor] |
8709 | The law of excluded middle is syntactic; it just says A or not-A, not whether they are true or false [Friend] |
8711 | Intuitionists read the universal quantifier as "we have a procedure for checking every..." [Friend] |
8675 | Paradoxes can be solved by talking more loosely of 'classes' instead of 'sets' [Friend] |
8674 | The Burali-Forti paradox asks whether the set of all ordinals is itself an ordinal [Friend] |
8667 | The 'integers' are the positive and negative natural numbers, plus zero [Friend] |
8668 | The 'rational' numbers are those representable as fractions [Friend] |
8670 | A number is 'irrational' if it cannot be represented as a fraction [Friend] |
8661 | The natural numbers are primitive, and the ordinals are up one level of abstraction [Friend] |
8664 | Cardinal numbers answer 'how many?', with the order being irrelevant [Friend] |
8671 | The 'real' numbers (rationals and irrationals combined) is the Continuum, which has no gaps [Friend] |
17730 | Combining the concepts of negation and finiteness gives the concept of infinity [Jenkins] |
8663 | Raising omega to successive powers of omega reveal an infinity of infinities [Friend] |
8662 | The first limit ordinal is omega (greater, but without predecessor), and the second is twice-omega [Friend] |
8669 | Between any two rational numbers there is an infinite number of rational numbers [Friend] |
8676 | Is mathematics based on sets, types, categories, models or topology? [Friend] |
8678 | Most mathematical theories can be translated into the language of set theory [Friend] |
8701 | The number 8 in isolation from the other numbers is of no interest [Friend] |
8702 | In structuralism the number 8 is not quite the same in different structures, only equivalent [Friend] |
8699 | Are structures 'ante rem' (before reality), or are they 'in re' (grounded in physics)? [Friend] |
8696 | Structuralist says maths concerns concepts about base objects, not base objects themselves [Friend] |
8695 | Structuralism focuses on relations, predicates and functions, with objects being inessential [Friend] |
8700 | 'In re' structuralism says that the process of abstraction is pattern-spotting [Friend] |
8681 | The big problem for platonists is epistemic: how do we perceive, intuit, know or detect mathematical facts? [Friend] |
17719 | Arithmetic concepts are indispensable because they accurately map the world [Jenkins] |
17717 | Senses produce concepts that map the world, and arithmetic is known through these concepts [Jenkins] |
8712 | Mathematics should be treated as true whenever it is indispensable to our best physical theory [Friend] |
17724 | It is not easy to show that Hume's Principle is analytic or definitive in the required sense [Jenkins] |
8716 | Formalism is unconstrained, so cannot indicate importance, or directions for research [Friend] |
8706 | Constructivism rejects too much mathematics [Friend] |
8707 | Intuitionists typically retain bivalence but reject the law of excluded middle [Friend] |
3747 | Events are fast changes which are of interest to us [O'Connor] |
17727 | We can learn about the world by studying the grounding of our concepts [Jenkins] |
17720 | There's essential, modal, explanatory, conceptual, metaphysical and constitutive dependence [Jenkins, by PG] |
17728 | The concepts we have to use for categorising are ones which map the real world well [Jenkins] |
8704 | Structuralists call a mathematical 'object' simply a 'place in a structure' [Friend] |
3743 | We can't contemplate our beliefs until we have expressed them [O'Connor] |
3748 | Without language our beliefs are particular and present [O'Connor] |
17726 | Examining accurate, justified or grounded concepts brings understanding of the world [Jenkins] |
17734 | It is not enough that intuition be reliable - we need to know why it is reliable [Jenkins] |
17723 | Knowledge is true belief which can be explained just by citing the proposition believed [Jenkins] |
8685 | Studying biology presumes the laws of chemistry, and it could never contradict them [Friend] |
8688 | Concepts can be presented extensionally (as objects) or intensionally (as a characterization) [Friend] |
17739 | The physical effect of world on brain explains the concepts we possess [Jenkins] |
17718 | Grounded concepts are trustworthy maps of the world [Jenkins] |
17731 | Verificationism is better if it says meaningfulness needs concepts grounded in the senses [Jenkins] |
17732 | Success semantics explains representation in terms of success in action [Jenkins] |
17725 | 'Analytic' can be conceptual, or by meaning, or predicate inclusion, or definition... [Jenkins] |