His failure to make anything of Dionysius did not lead Plato to abandon his efforts to heal the wounds of Hellenism. One of the studies most ardently pursued in the Academy was Jurisprudence, of which he is the real founder. It was not uncommon for Greek states to apply to the Academy for legislators to codify existing law or to frame a new code for colonies which had just been founded. That is the real explanation of the remarkable work entitled the _Laws_, which must have occupied Plato for many years, and which was probably begun while he was still directing the studies of Dionysius. It appears to have been left unfinished; for, while some parts of it are highly elaborated, there are others which make upon us the impression of being a first draft. Even so, it is a great work if we regard it from the proper point of view. It is, in the first place, a codification of Greek, and especially Athenian law, of course with those reforms and improvements which suggest themselves when the subject is systematically treated, and it formed the basis of Hellenistic, and through that of Roman law, to which the world owes so much. There is no more useful corrective of the popular notion of Plato as an unpractical visionary than the careful study of the dullest and most technical parts of the _Laws_ in the light of the _Institutes_. No attempt has been made here to describe the system of Plato as a whole, and indeed the time has not yet come when such an attempt can profitably be made. We have no direct knowledge of his teaching in the Academy; for we only possess the works which he wrote with a wider public in view. In the case of Aristotle (384-322 B. C.), a similar reservation must be made, though for just the opposite reason. We have only fragments of his published works and what we possess is mainly the groundwork of his lectures in the Lyceum. It will be seen that there is still very much to be done here too. From the nature of the case, notes for lectures take a great deal for granted that would be more fully explained when the lectures were delivered, and some of the most important points are hardly developed at all. Nevertheless there are certain things which come out clearly enough, and it so happens that they are points of great importance from which we can learn something with regard to the philosophical problems of the present day.