I.

In the preceding chapter we traced the rise and progress of physical philosophy among the ancient Greeks. We showed how a few great thinkers, borne on by an unparalleled development of intellectual activity, worked out ideas respecting the order of nature and the constitution of matter which, after more than two thousand years, still remain as fresh and fruitful as ever; and we found that, in achieving these results, Greek thought was itself determined¹ by ascertainable² laws. Whether controlling artistic³ imagination or penetrating⁴ to the objective truth of things, it remained always essentially⁵ homogeneous, and worked under the same forms of circumscription⁶, analysis, and opposition⁷. It began with external nature, and with a far distant past; nor could it begin otherwise, for only so could the subjects of its later meditations⁸ be reached. Only after less sacred beliefs have been shaken can ethical⁹ dogmas be questioned. Only when discrepancies¹⁰ of opinion obtrude¹¹ themselves on man’s notice is the need of an organising logic¹² experienced. And the mind’s eye, originally focussed for distant objects alone, has to be gradually restricted in its range by the pressure of accumulated experience before it can turn from past to present, from successive to contemporaneous