man as he now is, and with the changes in the organisation of his life that can be made during the next few centuries. It may be that some scores of generations hence, we shall have discovered that the improvements in government which can be brought about by such inquiry, are insignificant when compared with the changes which will be made possible when, through the hazardous experiment of selective breeding, we have altered the human type itself. But however anxious we are to see the facts of our existence without illusion, and to hope nothing without cause, we can still draw some measure of comfort from the recollection that during the few thousand years through which we can trace political history in the past, man, without changing his nature, has made enormous improvements in his polity, and that those improvements have often been the result of new moral ideals formed under the influence of new knowledge. The ultimate and wider effect on our conduct of any increase in our knowledge may indeed be very different from, and more important than, its immediate and narrower effect. We each of us live our lives in a pictured universe, of which only a small part is contributed by our own observation and memory, and by far the greater part by what we have learnt from others. The changes in that mental picture of our environment made for instance by the discovery of America, or the ascertainment of the true movements of the nearer heavenly bodies, exercised an influence on men's general conception of their place in the universe, which proved ultimately to be more important than their immediate effect in stimulating explorers and improving the art of navigation. But none of the changes of outlook in the past have approached in their extent and significance those which have been in progress during the last fifty years, the new history of man and his surroundings, stretching back through hitherto unthought-of ages, the substitution of an illimitable vista of ever changing worlds for the imagined perfection of the ordered heavens, and above all the intrusion of science into the most intimate regions of ourselves. The effects of such changes often come, it is true, more slowly than we hope. I was talking not long ago to one of the ablest of those who were beginning their intellectual life when Darwin published the _Origin of Species_. He told me how he and his philosopher brother expected that at once all things should become new, and how unwillingly as the years went on they had accepted their disappointment. But though slow, they are far-reaching.