This, and this alone, seems to me to afford a working hypothesis which is based on fact, can be brought into harmony with the existing environment, and embraces, in a wider synthesis, all that is good in other philosophies and religions. When I talk of our new environment, it requires one who, like the author, has lived more than the Scriptural threescore and ten years, and has, so to speak, one foot on the past and one on the present, to realise how enormous is the change which a single generation has made in the whole spiritual surroundings of a civilised man of the nineteenth century. When I was a student at Cambridge, little more than fifty years ago, Astronomy was the only branch of natural science which could be said to be definitely brought within the domain of natural law. And that only as regards the law of gravity, and the motions of the heavenly bodies, for little or nothing was known as to their constitution. Geology was just beginning the series of conquests by which time and the order and succession of life on the earth have been annexed by science as completely as space by astronomy; and theories of cataclysms, universal deluges, and special recent creations of animals and man, still held their ground, and were quoted as proofs of a universe maintained by constant supernatural interference. And when I say that space had been annexed to science by astronomy, it was really only that half of space which extends from the standpoint of the human senses in the direction of the infinitely great. The other equally important half which extends downwards to the infinitely small was unknown, or the subject only of the vaguest conjectures. Chemistry was, to a great extent, an empirical science, and molecules and atoms were at best guesses at truth, or rather convenient mathematical abstractions with no more actual reality than the symbols of the differential calculus. The real causes and laws of heat, light, and electricity, were as little known as those of molecular action and of chemical affinity. The great laws of the indestructibility of matter, the correlation of forces, and the conservation of energy, were unknown, or only just beginning to be foreshadowed. As regards life, protoplasm was a word unheard of; scientific biology, zoology, and botany were in their infancy; and the gradual building up of all living matter from a speck of protoplasm, through a primitive cell, was not even suspected. Above all, the works of Darwin had not been published, and evolution had not become the general law of modern thought; nor had the discovery of the antiquity of man, and of his slow development upwards from the rudest origins, shattered into fragments established beliefs as to his recent miraculous creation.