So the "Nature" which Greek life was seeking gets its deepest significance and reinterprets the old religious demand for unity of the life of man with the forces of the unseen. And the Stoic later, in his maxim "Follow Nature," gives more explicit recognition to the return of the circle. For the great work of Greek science had brought out into complete clearness the idea of Nature as a system of law. The universe is a rational universe, a cosmos, and man, as above all else a rational being, finds thus his kinship to the universe. To follow Nature, therefore, means to know the all-pervading law of Nature and submit to it in calm acceptance or resignation. "All is harmonious to me that is harmonious to thee, O universe; all is fruit to me which thy seasons bring."[80] § 6. THE CONCEPTION OF THE IDEAL =Contrast of Actual and Ideal.=--The two stages of Greek thought which we have sketched did more than to readjust Greek life to deeper views of the State and the individual; of the good and of nature. The very challenge and process brought into explicit consciousness a new feature of the moral life, which is fundamental to true moral consciousness, viz., the factor of contrast between the actual and the ideal. We have seen that the clash of one-sided interests and political institutions and, in the case of Plato, the tragic execution of Socrates, obliged Plato and Aristotle to admit that the actual State did not subserve the real purpose which they were forced to seek in social organization. Both Plato and Aristotle, therefore, draw the picture of a State that should serve the complete purposes of human development. And again, in the individual life, both the conception of the development of man's highest possibilities and the conception of a measure or standard for the conflicting desires and purposes lead on to a conception which shall embody not merely the existing status but the goal of yet unrealized purpose.