"Unity is perhaps the keynote of modern science. This means unity in time, for the present is but the outgrowth of the past, and the future of the present. It means of process, for there seems to be no sharp dividing line between organic and inorganic, physical and mental, mental and spiritual. . And the unity of modern science means also a growing tendency towards cooperation, so that by working together scientists discover much that would else have remained hid."