15 ideas
| 6950 | You can be rational with undetected or minor inconsistencies [Harman] |
| 6954 | A coherent conceptual scheme contains best explanations of most of your beliefs [Harman] |
| 14970 | Normal system K has five axioms and rules [Cresswell] |
| 14971 | D is valid on every serial frame, but not where there are dead ends [Cresswell] |
| 14972 | S4 has 14 modalities, and always reduces to a maximum of three modal operators [Cresswell] |
| 14973 | In S5 all the long complex modalities reduce to just three, and their negations [Cresswell] |
| 14976 | Reject the Barcan if quantifiers are confined to worlds, and different things exist in other worlds [Cresswell] |
| 17697 | The existence of an arbitrarily large number refutes the idea that numbers come from experience [Hilbert] |
| 17698 | Logic already contains some arithmetic, so the two must be developed together [Hilbert] |
| 14974 | A relation is 'Euclidean' if aRb and aRc imply bRc [Cresswell] |
| 14975 | A de dicto necessity is true in all worlds, but not necessarily of the same thing in each world [Cresswell] |
| 6955 | Enumerative induction is inference to the best explanation [Harman] |
| 6952 | Induction is 'defeasible', since additional information can invalidate it [Harman] |
| 6953 | All reasoning is inductive, and deduction only concerns implication [Harman] |
| 6951 | Ordinary rationality is conservative, starting from where your beliefs currently are [Harman] |