31 ideas
6675 | The heart has its reasons of which reason knows nothing [Pascal] |
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] |
10121 | Contradiction is not a sign of falsity, nor lack of contradiction a sign of truth [Pascal] |
7790 | If an argument is invalid, a truth tree will indicate a counter-example [Girle] |
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] |
22011 | The first principles of truth are not rational, but are known by the heart [Pascal] |
6681 | We only want to know things so that we can talk about them [Pascal] |
6676 | Painting makes us admire things of which we do not admire the originals [Pascal] |
6680 | It is a funny sort of justice whose limits are marked by a river [Pascal] |
6677 | Imagination creates beauty, justice and happiness, which is the supreme good [Pascal] |
6678 | We live for the past or future, and so are never happy in the present [Pascal] |
20732 | If man considers himself as lost and imprisoned in the universe, he will be terrified [Pascal] |
6682 | Majority opinion is visible and authoritative, although not very clever [Pascal] |
6679 | It is not good to be too free [Pascal] |
7455 | Pascal knows you can't force belief, but you can make it much more probable [Pascal, by Hacking] |
7457 | Pascal is right, but relies on the unsupported claim of a half as the chance of God's existence [Hacking on Pascal] |
7456 | The libertine would lose a life of enjoyable sin if he chose the cloisters [Hacking on Pascal] |
6684 | If you win the wager on God's existence you win everything, if you lose you lose nothing [Pascal] |
1513 | The Egyptians were the first to say the soul is immortal and reincarnated [Herodotus] |