At the present day, his works possess a double significance. They are important historically, alike as giving us an insight into the mind of the eighteenth century, and for the actual influence they have had on the course of events in Europe. Certainly no other writer of the time has exercised such an influence as his. He may fairly be called the parent of the romantic movement in art, letters and life; he affected profoundly the German romantics and Goethe himself; he set the fashion of a new introspection which has permeated nineteenth century literature; he began modern educational theory; and, above all, in political thought he represents the passage from a traditional theory rooted in the Middle Ages to the modern philosophy of the State. His influence on Kant's moral philosophy and on Hegel's philosophy of Right are two sides of the same fundamental contribution to modern thought. He is, in fact, the great forerunner of German and English Idealism. It would not be possible, in the course of a short introduction, to deal both with the positive content of Rousseau's thought and with the actual influence he has had on practical affairs. The statesmen of the French Revolution, from Robespierre downwards, were throughout profoundly affected by the study of his works. Though they seem often to have misunderstood him, they had on the whole studied him with the attention he demands. In the nineteenth century, men continued to appeal to Rousseau, without, as a rule, knowing him well or penetrating deeply into his meaning. "The _Social Contract_," says M. Dreyfus-Brisac, "is the book of all books that is most talked of and least read." But with the great revival of interest in political philosophy there has come a desire for the better understanding of Rousseau's work. He is again being studied more as a thinker and less as an ally or an opponent; there is more eagerness to sift the true from the false, and to seek in the _Social Contract_ the "principles of political right," rather than the great revolutionary's _ipse dixit_ in favour of some view about circumstances which he could never have contemplated. The _Social Contract_, then, may be regarded either as a document of the French Revolution, or as one of the greatest books dealing with political philosophy. It is in the second capacity, as a work of permanent value containing truth, that it finds a place among the world's great books. It is in that capacity also that it will be treated in this introduction. Taking it in this aspect, we have no less need of historical insight than if we came to it as historians pure and simple. To understand its value we must grasp its limitations; when the questions it answers seem unnaturally put, we must not conclude that they are meaningless; we must see if the answer still holds when the question is put in a more up-to-date form.