13 ideas
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] |
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] |
5996 | Critolaus redefined Aristotle's moral aim as fulfilment instead of happiness [Critolaus, by White,SA] |
20180 | A happy and joyous life must largely be a quiet life [Russell] |
20179 | Happiness involves enduring boredom, and the young should be taught this [Russell] |
20178 | Life is now more interesting, but boredom is more frightening [Russell] |
20176 | Boredom is an increasingly strong motivating power [Russell] |
20177 | Boredom always involves not being fully occupied [Russell] |