29 ideas
| 21406 | Because there is only one human reason, there can only be one true philosophy from principles [Kant] |
| 7798 | There are three axiom schemas for propositional logic [Girle] |
| 7786 | Propositional logic handles negation, disjunction, conjunction; predicate logic adds quantifiers, predicates, relations [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] |
| 7796 | Modal logics were studied in terms of axioms, but now possible worlds semantics is added [Girle] |
| 7788 | Modal logic has four basic modal negation equivalences [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] |
| 21081 | We are equipped with the a priori intuitions needed for the concept of right [Kant] |
| 5960 | When the soul is intelligent and harmonious, it is part of god and derives from god [Plutarch] |
| 21082 | A power-based state of nature may not be unjust, but there is no justice without competent judges [Kant] |
| 21089 | Monarchs have the highest power; autocrats have complete power [Kant] |
| 21086 | Hereditary nobility has not been earned, and probably won't be earned [Kant] |
| 21080 | Actions are right if the maxim respects universal mutual freedoms [Kant] |
| 21083 | Women have no role in politics [Kant] |
| 21407 | Equality is not being bound in ways you cannot bind others [Kant] |
| 21084 | In the contract people lose their rights, but immediately regain them, in the new commonwealth [Kant] |
| 21090 | If someone has largely made something, then they own it [Kant] |
| 21087 | Human life is pointless without justice [Kant] |
| 21088 | Justice asserts the death penalty for murder, from a priori laws [Kant] |
| 21085 | The church has a political role, by offering a supreme power over people [Kant] |