72 ideas
| 21634 | Metaphysics is (supposedly) first the ontology, then in general what things are like [Hofweber] |
| 21666 | 'Fundamentality' is either a superficial idea, or much too obscure [Hofweber] |
| 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] |
| 8705 | Anti-realists see truth as our servant, and epistemically contrained [Friend] |
| 21640 | 'It's true that Fido is a dog' conjures up a contrast class, of 'it's false' or 'it's unlikely' [Hofweber] |
| 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] |
| 21657 | Since properties can have properties, some theorists rank them in 'types' [Hofweber] |
| 8709 | The law of excluded middle is syntactic; it just says A or not-A, not whether they are true or false [Friend] |
| 21653 | Maybe not even names are referential, but are just by used by speakers to refer [Hofweber] |
| 21636 | 'Singular terms' are not found in modern linguistics, and are not the same as noun phrases [Hofweber] |
| 21637 | If two processes are said to be identical, that doesn't make their terms refer to entities [Hofweber] |
| 21643 | The inferential quantifier focuses on truth; the domain quantifier focuses on reality [Hofweber] |
| 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] |
| 21644 | Numbers are used as singular terms, as adjectives, and as symbols [Hofweber] |
| 21646 | The Amazonian Piraha language is said to have no number words [Hofweber] |
| 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] |
| 21665 | The fundamental theorem of arithmetic is that all numbers are composed uniquely of primes [Hofweber] |
| 21649 | How can words be used for counting if they are objects? [Hofweber] |
| 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] |
| 8712 | Mathematics should be treated as true whenever it is indispensable to our best physical theory [Friend] |
| 21647 | Logicism makes sense of our ability to know arithmetic just by thought [Hofweber] |
| 21648 | Neo-Fregeans are dazzled by a technical result, and ignore practicalities [Hofweber] |
| 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] |
| 21664 | Supervenience offers little explanation for things which necessarily go together [Hofweber] |
| 21660 | Reality can be seen as the totality of facts, or as the totality of things [Hofweber] |
| 21661 | There are probably ineffable facts, systematically hidden from us [Hofweber] |
| 8704 | Structuralists call a mathematical 'object' simply a 'place in a structure' [Friend] |
| 21652 | Our perceptual beliefs are about ordinary objects, not about simples arranged chair-wise [Hofweber] |
| 21663 | Counterfactuals are essential for planning, and learning from mistakes [Hofweber] |
| 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] |
| 21654 | The "Fido"-Fido theory of meaning says every expression in a language has a referent [Hofweber] |
| 21641 | Inferential role semantics is an alternative to semantics that connects to the world [Hofweber] |
| 21638 | Syntactic form concerns the focus of the sentence, as well as the truth-conditions [Hofweber] |
| 21658 | Properties can be expressed in a language despite the absence of a single word for them [Hofweber] |
| 21659 | 'Being taller than this' is a predicate which can express many different properties [Hofweber] |
| 21655 | Compositonality is a way to build up the truth-conditions of a sentence [Hofweber] |
| 21656 | Proposition have no content, because they are content [Hofweber] |
| 21635 | Without propositions there can be no beliefs or desires [Hofweber] |
| 21662 | Do there exist thoughts which we are incapable of thinking? [Hofweber] |
| 21645 | 'Semantic type coercion' is selecting the reading of a word to make the best sense [Hofweber] |
| 21639 | 'Background deletion' is appropriately omitting background from an answer [Hofweber] |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |