Different races take to different processes of controlling nature. Just as in the same society some individuals want to control the external nature, and others the internal, so, among races, some want to control the external nature, and others the internal. Some say that by controlling internal nature we control everything. Others that by controlling external nature we control everything. Carried to the extreme both are right, because in nature there is no such division as internal or external. These are fictitious limitations that never existed. The externalists and the internalists are destined to meet at the same point, when both reach the extreme of their knowledge. Just as a physicist, when he pushes his knowledge to its limits, finds it melting away into metaphysics, so a metaphysician will find that what he calls mind and matter are but apparent distinctions, the reality being One.