Perrault bases his thesis on those general considerations which we have met incidentally in earlier writers, and which were now almost commonplaces among those who paid any attention to the matter.  Knowledge advances with time and experience; perfection is not necessarily associated with antiquity; the latest comers have inherited from their predecessors and added new acquisitions of their own.  But Perrault has thought out the subject methodically, and he draws conclusions which have only to be extended to amount to a definite theory of the progress of knowledge.

A particular difficulty had done much to hinder a general admission of progressive improvement in the past.  The proposition that the posterior is better and the late comers have the advantage seemed to be incompatible with an obvious historical fact.  We are superior to the men of the dark ages in knowledge and arts.  Granted.  But will you say that the men of the tenth century were superior to the Greeks and Romans?  To this question—­on which Tassoni had already touched—­Perrault replies:  Certainly not.  There are breaches of continuity.  The sciences and arts are like rivers, which flow for part of their course underground, and then, finding an opening, spring forth as abundant as when they plunged beneath the earth.  Long wars, for instance, may force peoples to neglect studies and throw all their vigour into the more urgent needs of self-preservation; a period of ignorance may ensue but with peace and felicity knowledge and inventions will begin again and make further advances. [Footnote:  The passages in Perrault’s Parallele specially referred to in the text will be found in vol. i. pp. 35-7, 60-61, 67, 231-3.]

It is to be observed that he does not, claim any superiority in talents or brain power for the moderns.  On the contrary, he takes his stand on the principle which he had asserted in the “Age of Louis the Great,” that nature is immutable.  She still produces as great men as ever, but she does not produce greater.  The lions of the deserts of Africa in our days do not differ in fierceness from those the days of Alexander the Great, and the best men of all times are equal in vigour.  It is their work and productions that are unequal, and, given equally favourable conditions, the latest must be the best.  For science and the arts depend upon the accumulation of knowledge, and knowledge necessarily increases as time goes on.

But could this argument be applied to poetry and literary art, the field of battle in which the belligerents, including Perrault himself, were most deeply interested?  It might prove that the modern age was capable of producing poets and men of letter no less excellent than the ancient masters, but did it prove that their works must be superior?  The objection did not escape Perrault, and he answers it ingeniously.  It is the function of poetry and eloquence to please the human heart, and in order to please it we must