| 5998 | From the necessity of the past we can infer the impossibility of what never happens [Diod.Cronus, by White,MJ] |
| 17183 | Things are impossible if they imply contradiction, or their production lacks an external cause [Spinoza] |
| 3946 | A thing is shown to be impossible if a contradiction is demonstrated within its definition [Berkeley] |
| 9428 | Nothing we clearly imagine is absolutely impossible [Hume] |
| 23283 | Necessity implies possibility, but in experience it matters which comes first [Williams,B] |
| 16426 | How can we know the metaphysical impossibilities; the a posteriori only concerns this world [Chalmers] |
| 14377 | Possibilities are manifestations of some power, and impossibilies rest on no powers [Jacobs] |