74 ideas
14227 | We could refer to tables as 'xs that are arranged tablewise' [Inwagen] |
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] |
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] |
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] |
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] |
10662 | Mereology is 'nihilistic' (just atoms) or 'universal' (no restrictions on what is 'whole') [Inwagen, by Varzi] |
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] |
17587 | The 'Law' of Excluded Middle needs all propositions to be definitely true or definitely false [Inwagen] |
17558 | Variables are just like pronouns; syntactic explanations get muddled over dummy letters [Inwagen] |
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] |
17583 | There are no heaps [Inwagen] |
18201 | General principles can be obvious in mathematics, but bold speculations in empirical science [Parsons,C] |
17578 | I reject talk of 'stuff', and treat it in terms of particles [Inwagen] |
17582 | Singular terms can be vague, because they can contain predicates, which can be vague [Inwagen] |
17556 | Material objects are in space and time, move, have a surface and mass, and are made of some stuff [Inwagen] |
8264 | Maybe table-shaped particles exist, but not tables [Inwagen, by Lowe] |
17565 | Nihilism says composition between single things is impossible [Inwagen] |
14228 | If there are no tables, but tables are things arranged tablewise, the denial of tables is a contradiction [Liggins on Inwagen] |
14468 | Actions by artefacts and natural bodies are disguised cooperations, so we don't need them [Inwagen] |
17571 | Every physical thing is either a living organism or a simple [Inwagen] |
17562 | The statue and lump seem to share parts, but the statue is not part of the lump [Inwagen] |
17574 | If you knead clay you make an infinite series of objects, but they are rearrangements, not creations [Inwagen] |
17531 | I assume matter is particulate, made up of 'simples' [Inwagen] |
17560 | If contact causes composition, do two colliding balls briefly make one object? [Inwagen] |
17561 | If bricks compose a house, that is at least one thing, but it might be many things [Inwagen] |
17566 | I think parthood involves causation, and not just a reasonably stable spatial relationship [Inwagen] |
14230 | We can deny whole objects but accept parts, by referring to them as plurals within things [Inwagen, by Liggins] |
17557 | Special Composition Question: when is a thing part of something? [Inwagen] |
17564 | The essence of a star includes the released binding energy which keeps it from collapse [Inwagen] |
17575 | The persistence of artifacts always covertly involves intelligent beings [Inwagen] |
17577 | When an electron 'leaps' to another orbit, is the new one the same electron? [Inwagen] |
17589 | If you reject transitivity of vague identity, there is no Ship of Theseus problem [Inwagen] |
17588 | We should talk of the transitivity of 'identity', and of 'definite identity' [Inwagen] |
9723 | Sentences with 'if' are only conditionals if they can read as A-implies-B [Enderton] |
17572 | Actuality proves possibility, but that doesn't explain how it is possible [Inwagen] |
17579 | Counterparts reduce counterfactual identity to problems about similarity relations [Inwagen] |
17590 | A merely possible object clearly isn't there, so that is a defective notion [Inwagen] |
17591 | Merely possible objects must be consistent properties, or haecceities [Inwagen] |
17563 | The strong force pulls, but also pushes apart if nucleons get too close together [Inwagen] |
17559 | Is one atom a piece of gold, or is a sizable group of atoms required? [Inwagen] |
17586 | At the lower level, life trails off into mere molecular interaction [Inwagen] |
17568 | A tumour may spread a sort of life, but it is not a life, or an organism [Inwagen] |
17581 | Being part of an organism's life is a matter of degree, and vague [Inwagen] |
17584 | Some events are only borderline cases of lives [Inwagen] |
17569 | Unlike waves, lives are 'jealous'; it is almost impossible for them to overlap [Inwagen] |
17580 | One's mental and other life is centred on the brain, unlike any other part of the body [Inwagen] |
17570 | The chemical reactions in a human life involve about sixteen elements [Inwagen] |
17585 | Life is vague at both ends, but could it be totally vague? [Inwagen] |
17567 | A flame is like a life, but not nearly so well individuated [Inwagen] |
17576 | If God were to 'reassemble' my atoms of ten years ago, the result would certainly not be me [Inwagen] |
17573 | There is no reason to think that mere existence is a valuable thing [Inwagen] |