THIS book is the outcome of eight lectures delivered at the University of Chicago in April 1948. I wish to thank the "Committee on Social Thought" and its Chairman, Professor J. U. Nef, for the opportunity they gave me to return to a subject which has been in my mind for many years. I also wish to thank the editor of this series, Professor H. J. Paton, for allowing me to state, in a concise and straightforward manner, my own very personal views and conclusions about the "nature of natural law". I wish further to thank him, as well as Professor D. A. Binchy, Mrs. I. Henderson and especially Mr. C. G. Hardie, for many helpful suggestions with regard to language and style.
Yet, on the point of releasing this short essay, I cannot avoid some misgivings. I am well aware that the language in which I have tried to express my thoughts is altogether a different one from that which prevails among present-day philosophers and political theorists. I am not sure that I have always succeeded in avoiding the over-emphasis which is the great temptation for a Latin. Above all, I have no claims to make as to the novelty of my material. The book is a good example of what supercilious scholars here in Oxford call "tertiary writing". The results of my own work in the field of legal and political philosophy I have published in a number of books and articles both in English and in my native Italian. I have had little scruple in drawing heavily upon them. But neither have I hesitated to avail myself of the conclusions of better scholars than I am, wherever they seemed to me to carry weight and final authority. What little originality the book may possess must therefore lie in the statement of a case rather than in the production of the evidence. That case may or may not be accepted. It is my hope that I may at least have succeeded in making it worth hearing.
To account for the themes that have inspired me would require a separate volume. I have no doubt that they will be sufficiently apparent to the attentive reader. I would like to