The progress in inventions, to which science may look forward, is suggested.

The men of the City of the Sun "have already discovered the one art which the world seemed to lack--the art of flying; and they expect soon to invent ocular instruments which will enable them to see the invisible stars and auricular instruments for hearing the harmony of the spheres." Campanella's view of the present conditions and prospects of knowledge is hardly less sanguine than that of Bacon, and characteristically he confirms his optimism by astrological data.

"If you only knew what their astrologers say about the coming age.

Our times, they assert, have more history in a hundred years than the whole world in four thousand.

More books have been published in this century than in five thousand years before.