The discovery and establishment of this spiritual principle, as a universal reality which transcends nature and the spirit of man, and which to this natural and human world is as a law dictated from outside and from above, is the message of the Middle Ages, not in pure philosophy only, but in religion and ethics, in science and in the life of society. The Renaissance is the beginning of our modern world, inasmuch as it is, through the infinite variety of its artistic, social, religious, scientific manifestations, an effort to see that same spiritual principle no longer as a transcending reality, but as the active, immanent, all-pervading soul of immediate reality, both natural and human. The Ptolemaic cosmography, which is the visible form of mediæval thought, a system of the finite universe, of which the Earth is the centre, and which leaves an infinite space for the seat of the only real, transcending existences, beyond the compass of the heavenly spheres, and as if it were outside itself, loses its hold on the imagination, and therefore on the conscience of men, long before Copernicus and Galileo read in the skies a new system of an infinite universe, within which, or nowhere, the divine principle must live and work. The impulse towards the identification of the spirit with nature, on one side, and with man on the other, had been at work in Italian life and thought all through the Renaissance; but it is only at the end of that miraculous spring of Western civilization, between the close of the sixteenth and the beginning of the seventeenth century, that it expresses itself in the philosophies of Bruno and Campanella. Bruno presents himself as an expounder and defender of Copernican astronomy, and Campanella writes the apology of Galileo. And to each of them the scientific discoveries are much more than mere helps and suggestions for metaphysical speculation; they are the revelation, in one field of human thought, of a new logic which has to be recognized, in one form or another, as the fundamental principle of modern civilization. Both in Bruno and Campanella, inert remnants of the ancient and mediæval logic are still part of the structure in which their new intuitions try to express themselves; but such remnants are to be met with even in much later philosophers, and constantly reappear, as blind spots in the active process of thought, in the whole history of European philosophy down to our days. What is significant of each thinker, what marks him as the legitimate interpreter of the deepest spiritual life of his times, is not his system as a whole, but the particular new intuition on which in each case the system is founded: in Bruno, the conception of an infinite universe, and of the infinite life of God in the universe; in Campanella, the affirmation of the value of human experience and human consciousness, to which God is present _per tactum intrinsecum,_ intrinsically, and in which knowing and being coincide.