than one example of such a gradual metamorphosis has already presented itself in the course of our investigation, and others will occur in the sequel. Where distinctions of right and wrong are involved, it is of enormous practical importance that a definite meaning should be attached to words, and that they should not be allowed, at least without express agreement, to depart from the recognised acceptation: for such words, connoting as they do the approval or disapproval of mankind, exercise a powerful influence on conduct, so that their misapplication may lead to disastrous consequences. Where government by written law prevails the importance of defining ethical terms immediately becomes obvious, for, otherwise, personal rule would be restored under the disguise of judicial interpretation. Roman jurisprudence was the first attempt on a great scale to introduce a rigorous system of definitions into legislation. We have seen, in the preceding chapter, how it tended to put the conclusions of Greek naturalistic philosophy into practical shape. We now see how, on the formal side, its determinations are connected with the principles of Socrates. And we shall not undervalue this obligation if we bear in mind that the accurate wording of legal enactments is not less important than the essential justice of their contents. Similarly, the development of Catholic theology required that its fundamental conceptions should be progressively defined. This alone preserved the intellectual character of Catholicism in ages of ignorance and superstition, and helped to keep alive the reason by which superstition was eventually overthrown. Mommsen has called theology the bastard child of Religion and Science. It is something that, in the absence of the robuster parent, its features should be recalled and its tradition maintained even by an illegitimate offspring.