37 ideas
| 15063 | Some sentences depend for their truth on worldly circumstances, and others do not [Fine,K] |
| 13913 | The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward] |
| 13914 | Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward] |
| 13915 | Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward] |
| 13916 | Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward] |
| 13850 | In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward] |
| 13849 | Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward] |
| 13851 | Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward] |
| 13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
| 15078 | There are levels of existence, as well as reality; objects exist at the lowest level in which they can function [Fine,K] |
| 15072 | Bottom level facts are subject to time and world, middle to world but not time, and top to neither [Fine,K] |
| 15071 | Tensed and tenseless sentences state two sorts of fact, which belong to two different 'realms' of reality [Fine,K] |
| 12132 | Indiscernibility is a necessary and sufficient condition for identity [Brody] |
| 15834 | Brody bases sortal essentialism on properties required throughout something's existence [Brody, by Mackie,P] |
| 15075 | Modal features are not part of entities, because they are accounted for by the entity [Fine,K] |
| 12140 | Modern emphasis is on properties had essentially; traditional emphasis is on sort-defining properties [Brody] |
| 11895 | A sortal essence is a property which once possessed always possessed [Brody, by Mackie,P] |
| 12141 | Maybe essential properties are those which determine a natural kind? [Brody] |
| 12137 | De re essentialism standardly says all possible objects identical with a have a's essential properties [Brody] |
| 15065 | What it is is fixed prior to existence or the object's worldly features [Fine,K] |
| 12142 | Essentially, a has P, always had P, must have had P, and has never had a future without P [Brody] |
| 12143 | An object having a property essentially is equivalent to its having it necessarily [Brody] |
| 12144 | Essentialism is justified if the essential properties of things explain their other properties [Brody] |
| 15076 | Essential features of an object have no relation to how things actually are [Fine,K] |
| 12139 | Mereological essentialism says that every part that ensures the existence is essential [Brody] |
| 12135 | Interrupted objects have two first moments of existence, which could be two beginnings [Brody] |
| 15073 | Self-identity should have two components, its existence, and its neutral identity with itself [Fine,K] |
| 15074 | We would understand identity between objects, even if their existence was impossible [Fine,K] |
| 12130 | a and b share all properties; so they share being-identical-with-a; so a = b [Brody] |
| 15064 | Proper necessary truths hold whatever the circumstances; transcendent truths regardless of circumstances [Fine,K] |
| 15070 | It is the nature of Socrates to be a man, so necessarily he is a man [Fine,K] |
| 15069 | Possible worlds may be more limited, to how things might actually turn out [Fine,K] |
| 15068 | The actual world is a totality of facts, so we also think of possible worlds as totalities [Fine,K] |
| 12138 | Identity across possible worlds is prior to rigid designation [Brody] |
| 15077 | It is said that in the A-theory, all existents and objects must be tensed, as well as the sentences [Fine,K] |
| 15067 | A-theorists tend to reject the tensed/tenseless distinction [Fine,K] |
| 15066 | B-theorists say tensed sentences have an unfilled argument-place for a time [Fine,K] |