Progress then is not an accident, but a necessity. Civilisation is a part of nature, being a development of man's latent capabilities under the action of favourable circumstances which were certain at some time or other to occur. Here Spencer's argument assumes a final cause. The ultimate purpose of creation, he asserts, is to produce the greatest amount of happiness, and to fulfil this aim it is necessary that each member of the race should possess faculties enabling him to experience the highest enjoyment of life, yet in such a way as not to diminish the power of others to receive like satisfaction. Beings thus constituted cannot multiply in a world tenanted by inferior creatures; these, therefore, must be dispossessed to make room; and to dispossess them aboriginal man must have an inferior constitution to begin with; he must be predatory, he must have the desire to kill. In general, given an unsubdued earth, and the human being "appointed" to overspread and occupy it, then, the laws of life being what they are, no other series of changes than that which has actually occurred could have occurred. The argument might be put in a form free from the assumption of a final cause, and without introducing the conception of a divine Providence which in this work Spencer adopted, though in his later philosophy it was superseded by the conception of the Unknowable existing behind all phenomena. But the ROLE of the Divine ruler is simply to set in motion immutable forces to realise his design. "In the moral as in the material world accumulated evidence is gradually generating the conviction that events are not at bottom fortuitous, but that they are wrought out in a certain inevitable way by unchanging forces." The optimism of Spencer's view could not be surpassed. "After patient study," he writes, "this chaos of phenomena into the midst of which he [man] was born has begun to generalise itself to him"; instead of confusion he begins to discern "the dim outlines of a gigantic plan. No accidents, no chance, but everywhere order and completeness One by one exceptions vanish, and all becomes systematic." Always towards perfection is the mighty movement--towards a complete development and a more unmixed good; subordinating in its universality all petty irregularities and fallings back, as the curvature of the earth subordinates mountains and valleys. Even in evils the student learns to recognise only a struggling beneficence. But above all he is struck with the inherent sufficingness of things.