64 ideas
18486 | We might define truth as arising from the truth-maker relation [MacBride] |
18484 | Phenomenalists, behaviourists and presentists can't supply credible truth-makers [MacBride] |
18466 | If truthmaking is classical entailment, then anything whatsoever makes a necessary truth [MacBride] |
18473 | 'Maximalism' says every truth has an actual truthmaker [MacBride] |
18481 | Maximalism follows Russell, and optimalism (no negative or universal truthmakers) follows Wittgenstein [MacBride] |
18483 | The main idea of truth-making is that what a proposition is about is what matters [MacBride] |
18479 | There are different types of truthmakers for different types of negative truth [MacBride] |
18477 | There aren't enough positive states out there to support all the negative truths [MacBride] |
18482 | Optimalists say that negative and universal are true 'by default' from the positive truths [MacBride] |
18474 | Does 'this sentence has no truth-maker' have a truth-maker? Reductio suggests it can't have [MacBride] |
18485 | Even idealists could accept truthmakers, as mind-dependent [MacBride] |
18490 | Maybe 'makes true' is not an active verb, but just a formal connective like 'because'? [MacBride] |
18493 | Truthmaker talk of 'something' making sentences true, which presupposes objectual quantification [MacBride] |
9724 | Until the 1960s the only semantics was truth-tables [Enderton] |
9703 | 'dom R' indicates the 'domain' of objects having a relation [Enderton] |
9705 | 'fld R' indicates the 'field' of all objects in the relation [Enderton] |
9704 | 'ran R' indicates the 'range' of objects being related to [Enderton] |
9710 | We write F:A→B to indicate that A maps into B (the output of F on A is in B) [Enderton] |
9707 | 'F(x)' is the unique value which F assumes for a value of x [Enderton] |
13201 | ∈ says the whole set is in the other; ⊆ says the members of the subset are in the other [Enderton] |
9712 | A relation is 'symmetric' on a set if every ordered pair has the relation in both directions [Enderton] |
9713 | A relation is 'transitive' if it can be carried over from two ordered pairs to a third [Enderton] |
13204 | The 'ordered pair' <x,y> is defined to be {{x}, {x,y}} [Enderton] |
13206 | A 'linear or total ordering' must be transitive and satisfy trichotomy [Enderton] |
9699 | The 'powerset' of a set is all the subsets of a given set [Enderton] |
9700 | Two sets are 'disjoint' iff their intersection is empty [Enderton] |
9702 | A 'domain' of a relation is the set of members of ordered pairs in the relation [Enderton] |
9701 | A 'relation' is a set of ordered pairs [Enderton] |
9706 | A 'function' is a relation in which each object is related to just one other object [Enderton] |
9708 | A function 'maps A into B' if the relating things are set A, and the things related to are all in B [Enderton] |
9709 | A function 'maps A onto B' if the relating things are set A, and the things related to are set B [Enderton] |
9711 | A relation is 'reflexive' on a set if every member bears the relation to itself [Enderton] |
9714 | A relation satisfies 'trichotomy' if all pairs are either relations, or contain identical objects [Enderton] |
9717 | A set is 'dominated' by another if a one-to-one function maps the first set into a subset of the second [Enderton] |
13200 | Note that {Φ} =/= Φ, because Φ ∈ {Φ} but Φ ∉ Φ [Enderton] |
13199 | The empty set may look pointless, but many sets can be constructed from it [Enderton] |
13203 | The singleton is defined using the pairing axiom (as {x,x}) [Enderton] |
9715 | An 'equivalence relation' is a reflexive, symmetric and transitive binary relation [Enderton] |
9716 | We 'partition' a set into distinct subsets, according to each relation on its objects [Enderton] |
13202 | Fraenkel added Replacement, to give a theory of ordinal numbers [Enderton] |
13205 | We can only define functions if Choice tells us which items are involved [Enderton] |
9722 | Inference not from content, but from the fact that it was said, is 'conversational implicature' [Enderton] |
9718 | Validity is either semantic (what preserves truth), or proof-theoretic (following procedures) [Enderton] |
18489 | Connectives link sentences without linking their meanings [MacBride] |
18476 | 'A is F' may not be positive ('is dead'), and 'A is not-F' may not be negative ('is not blind') [MacBride] |
9721 | A logical truth or tautology is a logical consequence of the empty set [Enderton] |
9994 | A truth assignment to the components of a wff 'satisfy' it if the wff is then True [Enderton] |
9719 | A proof theory is 'sound' if its valid inferences entail semantic validity [Enderton] |
9720 | A proof theory is 'complete' if semantically valid inferences entail proof-theoretic validity [Enderton] |
9995 | Proof in finite subsets is sufficient for proof in an infinite set [Enderton] |
9996 | Expressions are 'decidable' if inclusion in them (or not) can be proved [Enderton] |
9997 | For a reasonable language, the set of valid wff's can always be enumerated [Enderton] |
8923 | Numbers are identified by their main properties and relations, involving the successor function [MacBride] |
8926 | For mathematical objects to be positions, positions themselves must exist first [MacBride] |
18480 | Maybe it only exists if it is a truthmaker (rather than the value of a variable)? [MacBride] |
18471 | Different types of 'grounding' seem to have no more than a family resemblance relation [MacBride] |
18472 | Which has priority - 'grounding' or 'truth-making'? [MacBride] |
18475 | Russell allows some complex facts, but Wittgenstein only allows atomic facts [MacBride] |
21354 | It may be that internal relations like proportion exist, because we directly perceive it [MacBride] |
21353 | Internal relations are fixed by existences, or characters, or supervenience on characters [MacBride] |
21352 | 'Multigrade' relations are those lacking a fixed number of relata [MacBride] |
18478 | Wittgenstein's plan to show there is only logical necessity failed, because of colours [MacBride] |
9723 | Sentences with 'if' are only conditionals if they can read as A-implies-B [Enderton] |
21006 | If women share rights with men, they will exhibit similar virtues [Wollstonecraft] |