IV.—Place and Doctrine
Buffon may justly be acclaimed as the first populariser of natural history. He was, however, unscientific in his opposition to systems, which, in point of fact, essentially elucidated the important doctrine that a continuous succession of forms runs throughout the animal kingdom. His recognition of this principle was, indeed, one of his greatest services to the science.
Another of his wise generalisations was that Nature proceeds by unknown gradations, and consequently cannot adapt herself to formal analysis, since she passes from one species to another, and often from one genus to another, by shades of difference so delicate as to be wholly imperceptible.
In Buffon's eyes Nature is an infinitely diversified whole which it is impossible to break up and classify. "The animal combines all the powers of Nature; the forces animating it are peculiarly its own; it wishes, does, resolves, works, and communicates by its senses with the most distant objects. One's self is a centre where everything agrees, a point where all the universe is reflected, a world in miniature." In natural history, accordingly, each animal or plant ought to have its own biography and description.
Life, Buffon also held, abides in organic molecules. "Living beings are made up of these molecules, which exist in countless numbers, which may be separated but cannot be destroyed, which pierce into brute matter, and, working there, develop, it may be animals, it may be plants, according to the nature of the matter in which they are lodged. These indestructible molecules circulate throughout the universe, pass from one being to another, minister to the continuance of life, provide for nutrition and the growth of the individual, and determine the reproduction of the species."
Buffon further taught that the quantity and quality of life pass from lower to higher stages—in Tennysonian phrase, men "rise on stepping-stones of their dead selves to higher things"—and showed the unity and structure of all beings, of whom man is the most perfect type.
It has been claimed that Buffon in a measure anticipated Lamarck and Darwin. He had already foreseen the mutability of species, but had not succeeded in proving it for varieties and races. If he asserted that the species of dog, jackal, wolf and fox were derived from a single one of these species, that the horse came from the zebra, and so on, this was far from being tantamount to a demonstration of the doctrine. In fact, he put forward the mutability of species rather as probable theory than as established truth, deeming it the corollary of his views on the succession and connection of beings in a continuous series.
Some case may be made out for regarding Buffon as the founder of zoogeography; at all events he was the earliest to determine the natural habitat of each species. He believed that species changed with climate, but that no kind was found throughout all the globe. Man alone has the privilege of being everywhere and always the same, because the human race is one. The white man (European or Caucasian), the black man (Ethiopian), the yellow man (Mongol), and the red man (American) are only varieties of the human species. As the Scots express it with wonted pith, "We're a' Jock Tamson's bairns."
As to his geological works, Buffon expounded two theories of the formation of the globe. In his "Théorie de la Terre" he supported the Neptunists, who attributed the phenomena of the earth to the action of water. In his "Epoques de la Nature" he amplified the doctrines of Leibniz, and laid down the following propositions: (1) The earth is elevated at the equator and depressed at the poles in accordance with the laws of gravitation and centrifugal force; (2) it possesses an internal heat, apart from that received from the sun; (3) its own heat is insufficient to maintain life; (4) the substances of which the earth is composed are of the nature of glass, or can be converted into glass as the result of heat and fusion—that is, are verifiable; (5) everywhere on the surface, including mountains, exist enormous quantities of shells and other maritime remains.
To the theses just enumerated Buffon added what he called the "monuments," or what Hugh Miller, a century later, more aptly described as the Testimony of the Rocks. From a consideration of all these things, Buffon at length arrived at his succession of the Epochs, or Seven Ages of Nature, namely: (1) the Age of fluidity, or incandescence, when the earth and planets assumed their shape; (2) the Age of cooling, or consolidation, when the rocky interior of the earth and the great vitrescible masses at its surface were formed; (3) the Age when the waters covered the face of the earth; (4) the Age when the waters retreated and volcanoes became active; (5) the Age when the elephant, hippopotamus, rhinoceros, and other giants roamed through the northern hemisphere; (6) the Age of the division of the land into the vast areas now styled the Old and the New Worlds; and (7) the Age when Man appeared.