Under such unfavourable auspices did philosophy find a home in Athens. The great maritime capital had drawn to itself every other species of intellectual eminence, and this could not fail to follow with the rest. But philosophy, although hitherto identified with mathematical and physical science, held unexhausted possibilities of development in reserve. According to a well-known legend, Thales once fell into a tank while absorbed in gazing at the stars. An old woman advised him to look at the tank in future, for there he would see the water and the stars as well. Others after him had got into similar difficulties, and might seek to evade them by a similar artifice. While busied with the study of cosmic evolution, they had stumbled unawares on some perplexing mental problems. Why do the senses suggest beliefs so much at variance with those arrived at by abstract reasoning? Why should reason be more trustworthy than sense? Why are the foremost Hellenic thinkers so hopelessly disagreed? What is the criterion of truth? Of what use are conclusions which cannot command universal assent? Or, granting that truth is discoverable, how can it be communicated to others? Such were some of the questions now beginning urgently to press for a solution. ‘I sought for myself,’ said Heracleitus in his oracular style. His successors had to do even more—to seek not only for themselves but for others; to study the beliefs, habits, and aptitudes of their hearers with profound sagacity, in order to win admission for the lessons they were striving to impart. And when a systematic investigation of human nature had once begun, it could not stop short with a mere analysis of the intellectual faculties; what a man did was after all so very much more important than what he knew, was, in truth, that which alone gave his knowledge any practical value whatever. Moral distinctions, too, were beginning to grow uncertain. When every other traditional belief had been shaken to its foundations, when men were taught to doubt the evidence of their own senses, it was not to be expected that the conventional laws of conduct, at no time very exact or consistent, would continue to be accepted on the authority of ancient usage. Thus, every kind of determining influences, internal and external, conspired to divert philosophy from the path which it had hitherto pursued, and to change it from an objective, theoretical study into an introspective, dialectic, practical discipline. VI.