Of this theory, his doctrine of the moral sciences was neither more nor less than the first legitimate application. Both its author and the majority of his commentators are using inaccurate language in describing it as a simple extension of the previous applications--a second instance, added to that of the mathematical sciences, already examined. In the mathematical sciences, the principle of the conversion of the true with the created had been applied in appearance only. The principle itself was original and sound: so was the theory of mathematics. But the connexion between the two truths was altogether artificial and false. What was lacking was, unless we are mistaken, an effective relation between the concept of God who creates the world and, as creating it, knows it, and that of the man who arbitrarily constructs a world of abstractions, and in doing so either knows nothing at all, or else, when he ceases to be a geometer or arithmetician and becomes a philosopher, when he is composing not Euclid's Elements but the theory of knowledge in the _De antiquissima,_ knows merely that his procedure is arbitrary. If the mathematical sciences construct their concepts as they please, if they produce not truth but definitions, they are as a matter of fact not sciences at all, nor any form of knowledge, and cannot be compared with the divine knowledge, the knowledge of actual reality. In mathematics, says Vico, "man, holding within himself an imaginary world of lines and numbers, operates in this world by abstraction just as God operates in the universe by reality." It is a luminous comparison; but perhaps its light is that of metaphor rather than logic. In the moral sciences, on the other hand, the comparison is so entirely logical that it should frankly be called coincidence. Human knowledge is qualitatively identical with divine, and knows the world of man equally well; it is, however, quantitatively more restricted, and does not extend like the divine to the world of nature. In the human field we no longer find the expedients of weakness, definitions and falsifications; knowledge is here at its highest point of concreteness. Man creates the human world, creates it by transforming himself into the facts of society: by thinking it he re-creates his own creations, traverses over again the paths he has already traversed, reconstructs the whole ideally, and thus knows it with full and true knowledge. Here is a real world; and of this world man is truly the God.