"Without world unification the species would destroy itself by the enlarged powers that had come to it. This, said the men of science, is no theory, no political alternative; it is a statement of fact. Men had to pool their political, economic and educational lives. There was no other way for them but a series of degenerative phases leading very plainly to extinction. They could not revert now. They had to go on - up or down. They had gone too far with civilisation and in societies, to sink back into a merely "animal life again. The hold of the primates on life had always been a precarious one. Except where they were under human protection all the other great apes were extinct. Now plainly man had to go on to a larger life, a planetary existence, or perish in his turn."