the subjective conception of a rational nature common to them all. These, again, are rooted in early Greek thought, and were already emerging into distinctness at the time of Socrates. Accordingly we find that Plato, having to compose a characteristic speech for the Sophist Hippias, makes him say that like-minded men are by nature kinsmen and friends to one another.[83] Nature, however, soon came to be viewed under a different aspect, and it was maintained, just as by some living philosophers, that her true law is the universal oppression of the weak by the strong. Then the idea of mind came in as a salutary corrective. It had supplied a basis for the ethics of Protagoras, and still more for the ethics of Socrates; it was now combined with its old rival by the Stoics, and from their union arose the conception of human nature as something allied with and illustrated by all other forms of animal life, yet capable, if fully developed, of rising infinitely above them. Nevertheless, the individual and the universal element were never quite reconciled in the Stoic ethics. The altruistic quality of justice was clearly perceived; but no attempt was made to show that all virtue is essentially social, and has come to be recognised as obligatory on the individual mainly because it conduces to the safety of the whole community. The learner was told to conquer his passions for his own sake rather than for the sake of others; and indulgence in violent anger, though more energetically denounced, was, in theory, placed on a par with immoderate delight or uncontrollable distress. So also, vices of impurity were classed with comparatively harmless forms of sensuality, and considered in reference, not to the social degradation of their victims, but to the spiritual defilement of their perpetrators.