Page:Popular Science Monthly Volume 5.djvu/478

462 But, indeed, so far as Mr. Darwin puts forth a theory at all, it is not that natural selection is the cause of species; but that slight accidental variations occur from some unknown or inexplicable cause; and that by natural selection the fittest of these will survive.

There is not so much difference after all between the two so-called theories as it is common to believe; the inexplicable accident brings them together at last. It is only the using of different words for the same notion. Variation, by slight accidental degrees, is quite as unphilosophical as the production of species, by decided saltus or springs, from some innate miraculous cause. Suppose, then, we drop the question of the origin of species and the cause of variation, and try to observe and understand the different stages of the growth and evolution of such living creatures as the earth is filled with, whether fittest or unfittest: would not this be much more consistent with the vocation of science? In itself it will be a delight, whether it solves anything or not.

Assuming matter and its law or properties—and remember, again, that without them it would not be matter—how, and by what steps, and stages, and degrees, has it put on the myriad forms of life?

We will not enter into those deeper speculations of philosophy which range every thing in unity or duality—which divide Nature into matter and force—or look upon the cosmos as one substance under two aspects, static and dynamic; and regard matter, in mathematical language, as composed of points in space and time; or, using purer ontological phrases, as centres of force or motion under the cosmical relations of time and space. Nor is it necessary to draw comparisons between these conceptions. They are but doctrines of method, and for certain purposes one may use either. Neither is this the place to dwell upon the forces, their correlation, and their unity; nor upon the principles of physics as a science. All this will be assumed as generally understood.

Matter we have; now life!

Suppose every thing prepared—a home, the earth, fitted to receive the invited guest; whence the mysterious power, vitality? The altar is prepared, the wood cleaved, and the sacrifice laid thereon: how was the fire from heaven invoked?

Recollect this maxim of even the old scholastic philosophy: that, having matter and form—that is, Nature and its laws—we are not to search outside of these, for we need no other factors to account for all the metamorphoses this basement matter may assume.

The first appearance of organic life—the stealing of this first fire from heaven—this is the easiest step in the whole process; easiest, naturally, because nearest to the inorganic kingdom, which is so much less complicated than the organic; easiest, because, as we advance, the factors which enter into the calculation and bear upon the result become so numerous and obscure that we never can know when we