Note 38 — THE DEVELOPMENT HYPOTHESIS IN ITS EMBRYONIC STATE. OLDER THAN ITS ALLEGED FOUNDATIONS.

We are supplied with a curious example of that ever-returning cycle of speculation in which the human mind operates, by not only the introduction of the principle of Epicurus into the “Vestiges,” but also by the unconscious employment of even his very arguments, slightly modified by the floating semi-scientific notions of the time. The following passages, taken, the one from the modern work, the other from Fénélon’s life of the old Greek philosopher, are not unworthy of being studied, as curiously illustrative of the cycle of thought. Epicurus, I must, however, first remind the reader, in the words of his biographer, “supposed that men, and all other animals, were originally produced by the ground. According to him, the primitive earth was fat and nitrous; and the sun, gradually warming it, soon covered it with herbage and shrubs: there also began to arise on the surface of the ground a great number of small tumors like mushrooms, which having in a certain time come to maturity, the skin burst, and there came forth little animals, which, gradually retiring from the place where they were produced, began to respire.” And there can be little doubt, that had the microscope been a discovery of early Greece, the passage here would have told us, not of mushroom-like tumors, but of monads. Save that the element of microscopic fact is awanting in the one and present in the other, the following are strictly parallel lines of argument:—

“To the natural objection that the earth does not now produce men, lions, and dogs, Epicurus replies that the fecundity of the earth is now exhausted. In advanced age a woman ceases to bear children; a piece of land never before cultivated produces much more during the few first years than it does afterwards; and when a forest is once cut down, the soil never produces trees equal to those which have been rooted up. Those which are afterwards planted become dwarfish, and are perpetually degenerating. We are, however, he argues, by no means certain but there may be at present rabbits, hares, foxes, bears, and other animals, produced by the earth in their perfect state. The reason why we are backward in admitting it is, that it happens in retired places, and never falls under our view; and, never seeing rats but such as have been produced by other rats, we adopt the opinion that the earth never produced any.” (Fénélon’s Lives of the Ancient Philosophers.)

“In the first place, there is no reason to suppose that, though life had been imparted by natural means, after the first cooling of the surface to a suitable temperament, it would continue thereafter to be capable of being imparted in like manner. The great work of the peopling of this globe with living species is mainly a fact accomplished: the highest known species came as a crowning effort thousands of years ago. The work being thus to all appearance finished, we are not necessarily to expect that the origination of life and of species should be conspicuously exemplified in the present day. We are rather to expect that the vital phenomena presented to our eyes should mainly, if not entirely, be limited to a regular and unvarying succession of races by the ordinary means of generation. This, however, is no more an argument against a time when phenomena of the first kind prevailed, than it would be a proof against the fact of a mature man having once been a growing youth, that he is now seen growing no longer..... Secondly, it is far from being certain that the primitive imparting of life and form to inorganic elements is not a fact of our times.” (Vestiges of Creation.)