42 ideas
10888 | Sets can be defined by 'enumeration', or by 'abstraction' (based on a property) [Zalabardo] |
10889 | The 'Cartesian Product' of two sets relates them by pairing every element with every element [Zalabardo] |
10890 | A 'partial ordering' is reflexive, antisymmetric and transitive [Zalabardo] |
10886 | Determinacy: an object is either in a set, or it isn't [Zalabardo] |
10887 | Specification: Determinate totals of objects always make a set [Zalabardo] |
10897 | A first-order 'sentence' is a formula with no free variables [Zalabardo] |
10899 | Γ |= φ if φ is true when all of Γ is true, for all structures and interpretations [Zalabardo] |
10893 | Γ |= φ for sentences if φ is true when all of Γ is true [Zalabardo] |
10896 | Propositional logic just needs ¬, and one of ∧, ∨ and → [Zalabardo] |
5824 | How can an expression be a name, if names can change their denotation? [Evans] |
9038 | We must distinguish what the speaker denotes by a name, from what the name denotes [Evans] |
9042 | A private intention won't give a name a denotation; the practice needs it to be made public [Evans] |
9041 | The Causal Theory of Names is wrong, since the name 'Madagascar' actually changed denotation [Evans] |
10898 | The semantics shows how truth values depend on instantiations of properties and relations [Zalabardo] |
10902 | We can do semantics by looking at given propositions, or by building new ones [Zalabardo] |
10892 | We make a truth assignment to T and F, which may be true and false, but merely differ from one another [Zalabardo] |
10895 | 'Logically true' (|= φ) is true for every truth-assignment [Zalabardo] |
10900 | Logically true sentences are true in all structures [Zalabardo] |
10894 | A sentence-set is 'satisfiable' if at least one truth-assignment makes them all true [Zalabardo] |
10901 | Some formulas are 'satisfiable' if there is a structure and interpretation that makes them true [Zalabardo] |
10903 | A structure models a sentence if it is true in the model, and a set of sentences if they are all true in the model [Zalabardo] |
10891 | If a set is defined by induction, then proof by induction can be applied to it [Zalabardo] |
8628 | I hold that algebra and number are developments of logic [Jevons] |
16129 | Evans argues (falsely!) that a contradiction follows from treating objects as vague [Evans, by Lowe] |
16459 | Is it coherent that reality is vague, identities can be vague, and objects can have fuzzy boundaries? [Evans] |
16460 | Evans assumes there can be vague identity statements, and that his proof cannot be right [Evans, by Lewis] |
16457 | There clearly are vague identity statements, and Evans's argument has a false conclusion [Evans, by Lewis] |
14484 | If a=b is indeterminate, then a=/=b, and so there cannot be indeterminate identity [Evans, by Thomasson] |
16224 | There can't be vague identity; a and b must differ, since a, unlike b, is only vaguely the same as b [Evans, by PG] |
14895 | 'Superficial' contingency: false in some world; 'Deep' contingency: no obvious verification [Evans, by Macią/Garcia-Carpentiro] |
11881 | Rigid designators can be meaningful even if empty [Evans, by Mackie,P] |
7639 | The Homunculus Fallacy explains a subject perceiving objects by repeating the problem internally [Evans] |
7643 | We have far fewer colour concepts than we have discriminations of colour [Evans] |
12580 | Experiences have no conceptual content [Evans, by Greco] |
23794 | Some representational states, like perception, may be nonconceptual [Evans, by Schulte] |
16366 | The Generality Constraint says if you can think a predicate you can apply it to anything [Evans] |
12575 | Concepts have a 'Generality Constraint', that we must know how predicates apply to them [Evans, by Peacocke] |
5825 | Speakers intend to refer to items that are the source of their information [Evans] |
5823 | The intended referent of a name needs to be the cause of the speaker's information about it [Evans] |
9039 | If descriptions are sufficient for reference, then I must accept a false reference if the descriptions fit [Evans] |
9043 | We use expressions 'deferentially', to conform to the use of other people [Evans] |
9040 | Charity should minimize inexplicable error, rather than maximising true beliefs [Evans] |