The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt. Even those of the intelligent who believe that they have a nostrum are too individualistic to combine with other intelligent men from whom they differ on minor points. This was not always the case. A hundred years ago the philosophical radicals formed a school of intelligent men who were just as sure of themselves as the Hitlerites are; the result was that they dominated politics and that the world advanced rapidly both in intelligence and in material well-being.
It is quite true that the intelligence of the philosophical radicals was very limited. It is, I think, undeniable that the best men of the present day have a wider and truer outlook, but the best men of that day had influence, while the best men of this are impotent spectators. Perhaps we shall have to realise that scepticism and intellectual individualism are luxuries which in our tragic age must be forgone, and if intelligence is to be effective, it will have to be combined with a moral fervour which it usually possessed in the past but now usually lacks.
If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.