24 ideas
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] |
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] |
5078 | Kant and Mill both try to explain right and wrong, without a divine lawgiver [Taylor,R] |
5067 | Morality based on 'forbid', 'permit' and 'require' implies someone who does these things [Taylor,R] |
5079 | Pleasure can have a location, and be momentary, and come and go - but happiness can't [Taylor,R] |
5068 | 'Eudaimonia' means 'having a good demon', implying supreme good fortune [Taylor,R] |
5076 | To Greeks it seemed obvious that the virtue of anything is the perfection of its function [Taylor,R] |
7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
5077 | The modern idea of obligation seems to have lost the idea of an obligation 'to' something [Taylor,R] |
5066 | If we are made in God's image, pursuit of excellence is replaced by duty to obey God [Taylor,R] |
5065 | The ethics of duty requires a religious framework [Taylor,R] |