29 ideas
10170 | While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price] |
16186 | The Barcan Formulas express how to combine modal operators with classical quantifiers [Simchen] |
16187 | The Barcan Formulas are orthodox, but clash with the attractive Actualist view [Simchen] |
16190 | BF implies that if W possibly had a child, then something is possibly W's child [Simchen] |
10166 | ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price] |
10175 | Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price] |
10165 | 'Analysis' is the theory of the real numbers [Reck/Price] |
10174 | Mereological arithmetic needs infinite objects, and function definitions [Reck/Price] |
10164 | Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price] |
10172 | Set-theory gives a unified and an explicit basis for mathematics [Reck/Price] |
10167 | Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price] |
10169 | Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price] |
10179 | There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price] |
10181 | Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price] |
10182 | There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price] |
10168 | Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price] |
10178 | Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price] |
10176 | Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price] |
10177 | Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price] |
10171 | The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price] |
10173 | A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price] |
16188 | Serious Actualism says there are no facts at all about something which doesn't exist [Simchen] |
6968 | Some people think there are ethical facts, but of a 'queer' sort [Ayer] |
6972 | A right attitude is just an attitude one is prepared to stand by [Ayer] |
6973 | Moral theories are all meta-ethical, and are neutral as regards actual conduct [Ayer] |
6974 | Moral judgements cannot be the logical consequence of a moral philosophy [Ayer] |
6971 | I would describe intuitions of good as feelings of approval [Ayer] |
6969 | Approval of historical or fictional murders gives us leave to imitate them [Ayer] |
6970 | Moral judgements are not expressions, but are elements in a behaviour pattern [Ayer] |