Let me point out in this respect that insufficient attention is perhaps paid to the fact that there are always only a very tiny number of instances in history on which are built up a ‘law’, which claims to be valid for the whole past and future evolution of humanity. Vico says that history is a series of alternations between periods of progress and periods of retrogression; and he gives _two_ examples. Saint-Simon says history is a series of oscillations between organic epochs and critical epochs; and he gives _two_ examples. Marx says history is a series of economic systems, each of which casts out its predecessor by means of violence; and he gives _one_ example! I shall be told that these examples could not be more numerous, owing to the fact that history, at least known history, is so short. The truth, implied by this very reply, is that history has lasted too short a time for us to be able to deduce laws from it to enable us to infer the future from the past. Those who do so are like a mathematician who should decide the nature of a curve from the form he finds it has at its very beginning. True, a somewhat uncommon turn of mind is required to confess that human history, after several thousands of years, is only beginning. I cannot sufficiently admire the rare mental value displayed by La Bruyère (in my opinion) when he wrote the following lines in a century which was strongly inclined to think it was the topmost summit of human development: ‘If the world lasts only a hundred million years, it will still be in all its freshness and only beginning; we ourselves are almost contemporary with the first men and the patriarchs, and who, in those far-off ages, will be able to avoid confusing us with them? But if we judge of the future from the past, what new things are we ignorant of in the arts, in the sciences, in Nature, and, I dare say, in history? What discoveries will be made! What different revolutions will occur in our Empires all over the world! How ignorant we are! And how slight is an experience of six or seven thousand years!’