39 ideas
| 3656 | The greatest good for a state is true philosophers [Descartes] |
| 7786 | Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [Girle] |
| 7798 | There are three axiom schemas for propositional logic [Girle] |
| 7799 | Proposition logic has definitions for its three operators: or, and, and identical [Girle] |
| 7797 | Axiom systems of logic contain axioms, inference rules, and definitions of proof and theorems [Girle] |
| 7794 | There are seven modalities in S4, each with its negation [Girle] |
| 7793 | ◊p → □◊p is the hallmark of S5 [Girle] |
| 7795 | S5 has just six modalities, and all strings can be reduced to those [Girle] |
| 7787 | Possible worlds logics use true-in-a-world rather than true [Girle] |
| 7788 | Modal logic has four basic modal negation equivalences [Girle] |
| 7796 | Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle] |
| 7789 | Necessary implication is called 'strict implication'; if successful, it is called 'entailment' [Girle] |
| 7790 | If an argument is invalid, a truth tree will indicate a counter-example [Girle] |
| 16744 | All powers can be explained by obvious features like size, shape and motion of matter [Descartes] |
| 5016 | Five universals: genus, species, difference, property, accident [Descartes] |
| 5015 | A universal is a single idea applied to individual things that are similar to one another [Descartes] |
| 16630 | If we perceive an attribute, we infer the existence of some substance [Descartes] |
| 5013 | A substance needs nothing else in order to exist [Descartes] |
| 16633 | A substance has one principal property which is its nature and essence [Descartes] |
| 7800 | Analytic truths are divided into logically and conceptually necessary [Girle] |
| 7801 | Possibilities can be logical, theoretical, physical, economic or human [Girle] |
| 7792 | A world has 'access' to a world it generates, which is important in possible worlds semantics [Girle] |
| 3658 | Total doubt can't include your existence while doubting [Descartes] |
| 5005 | I think, therefore I am, because for a thinking thing to not exist is a contradiction [Descartes] |
| 5006 | 'Thought' is all our conscious awareness, including feeling as well as understanding [Descartes] |
| 5012 | 'Nothing comes from nothing' is an eternal truth found within the mind [Descartes] |
| 5004 | We can know basic Principles without further knowledge, but not the other way round [Descartes] |
| 5014 | We can understand thinking occuring without imagination or sensation [Descartes] |
| 5017 | In thinking we shut ourselves off from other substances, showing our identity and separateness [Descartes] |
| 5010 | Our free will is so self-evident to us that it must be a basic innate idea [Descartes] |
| 5011 | There are two ultimate classes of existence: thinking substance and extended substance [Descartes] |
| 5018 | Even if tightly united, mind and body are different, as God could separate them [Descartes] |
| 5007 | Most errors of judgement result from an inaccurate perception of the facts [Descartes] |
| 5009 | We do not praise the acts of an efficient automaton, as their acts are necessary [Descartes] |
| 5008 | The greatest perfection of man is to act by free will, and thus merit praise or blame [Descartes] |
| 20930 | The existence of law is one thing, its merits and demerits another [Austin,J] |
| 15987 | Physics only needs geometry or abstract mathematics, which can explain and demonstrate everything [Descartes] |
| 12730 | We will not try to understand natural or divine ends, or final causes [Descartes] |
| 16601 | Matter is not hard, heavy or coloured, but merely extended in space [Descartes] |