ing Nature's secrets. The difference between Rousseau, who admired the simple life, and Condorcet, who believed in modern civilization, was no new one; it was a common theme of discussion in antiquity, and the ancients were well aware that the same process may be called either progress or decline. As Freeman says, 'In history every step in advance has also been a step backwards'. (The picture is a little difficult to visualize, but the meaning is plain.) The fruit of the tree of knowledge, always drives man from some paradise or other; and even the paradise of fools is not an unpleasant abode while it is habitable. Few emblematic pictures are more striking than the Melencolia (as he spells it) of Dürer, representing the Spirit of the race sitting mournfully among all her inventions: and this was at the beginning of the age of discovery! But the deepest thought of antiquity was neither optimistic nor pessimistic. It was that progress and retrogression are only the incoming and outgoing tide in an unchanging sea. The pulse of the universe beats in an alternate expansion and contraction. The result is a series of cycles, in which history repeats itself. Plato contemplates a world-cycle of 36,000 solar years, during which the Creator guides the course of events; after which he relaxes his hold of the machine, and a period of the same length follows, during which the world gradually degenerates. When this process is complete, the Creator restores again the original conditions, and a new cycle begins. Aristotle thinks that all the arts and sciences have been discovered and lost 'an infinite number of times'. Virgil in the Fourth Eclogue tries to please Augustus by predicting the near approach of a new golden age, which, he says, is now due. This doctrine of recurrence is not popular to-day; but
