so far as we can trace back and uncover their roots, the roots imitating sounds and the interjectional roots form only a small and entirely isolated minority, which neither shares in, nor is capable of development; they stand like "dead sticks in a live hedge." By far the greater number of roots, and all which are capable of development, express abstractions from visible objects, conditions and activities, and therefore presume a human intelligence, reflecting with self-consciousness, which formed and used the roots.
Now Max Müller sees, back of this period, still open to science, in which the root-elements of the human languages were fixed, a long period of exuberant and unhindered growth of the elements of language, in which the roots were separated from the multitude of nascent tones by elimination or natural selection in the struggle for existence. In this realm, which is no longer open to investigation, the naturalistic and the linguistic friends of the evolution theory are now in entire accord. Wilhelm Bleek, in his small, but very noteworthy essay, "Ueber den Ursprung der Sprache" ("Origin of Language"), Weimar, Böhlau, 1868, p. 11, uses this ingenious figure: what the animal world possesses analogous to language, takes about the same position as, in the art of printing, the block-print does in relation to printing with movable types. On page 12, he sees in the communication of the emotions among animals the sources from which under favorable conditions (in consequence of which the separation of language into articulated parts became possible) human language might have originated. This idea, which is closely joined to the interjectional theory, Darwin meets
with a related idea, depending upon the onomatopoetical theory, when he says, in his "Descent of Man": "Since monkeys certainly understand much that is said to them by man, and when wild, utter signal-cries of danger to their fellows, may not some unusually wise ape-like animal have imitated the growl of a beast of prey, and thus told his fellow-monkeys the nature of the expected danger? This would have been a first step in the formation of language."
But philology, from the point where it goes farther back in search of the roots of language, leaves the safe ground of knowledge and commits itself to the fluctuating ocean of conjectures; and since also the scientific evolution theory has only a hypothetical value, the support of a hypothesis in the one science by a hypothesis in the other naturally adds no weight to its probability, either for the one or the other. Besides, we must not overlook the fact that the very point in the history of the development of languages on which the investigation, as it looks backwards, must at present pause—namely, the existence of linguistic roots—presumes a faculty of abstraction which can not be thought of without self-consciousness.
Therefore archæology, comparative ethnography, and comparative philology, show us quite clearly a development, but not an origin of mankind through development. Yet they do show an already existing development of mankind; for all three sciences lead back to starting-points, where mankind already existed with all the essential attributes of mankind, and leave us without answer to our questions as to the conditions lying still farther back. Their results we can
without difficulty harmonize with a theory which supposes mankind to have originated by evolution, provided such a theory could be confirmed from another side; but they agree just as well with a contrary theory, which excludes the origin of mankind by gradual development.
Taking, thus, everything into consideration, we come to the conclusion that the evolution theory, like the descent theory, is so far only a hypothesis—and, indeed, a hypothesis which as such has a much more problematical character than the descent theory. For while in regard to the latter we had to say that we have either this explanation or none of the origin of the higher species, with the evolution theory there is not even room for this alternative. For even in case of its failure, a descent of one species from another through heterogenetic generation is certainly very possible. Besides, it is not only possible, but even probable, that both theories—that of heterogenetic generation and that of gradual development—may have to share with one another in the explanation of the origin of species; and even that, especially for the lowest species and for the beginnings of the main types, primitive generation also has its share in the establishment of the paternity.
The evolution theory could only pass beyond the rank of a hypothesis, if we should succeed in showing the impelling forces of such an origin of species through development. Such an attempt can be made in two ways—the metaphysical and the scientific-empirical. The first, the metaphysical, although it may be justified in its general principles, will always, from the point at which it attempts to approach the concrete questions as
to the origin of single species, expose itself to the fate of being a priori rejected by science as unjustified, and of being a posteriori confuted by facts—a fate which it has richly and clearly experienced in the first half of our century. But the discussion of the metaphysical way does not belong to the present purely scientific part of our investigation; it will, however, be shortly taken up again in Book II. The other way, the scientific-empirical, will have to be looked upon as correct when it can show the impelling forces of development in such powers and laws as are either still active to-day or at least have their points of connection in powers and laws active to-day. Such an attempt is the selection theory. We have already in Chap. II, [§ 1] and [2], given an outline of this theory, and have only yet to discuss its present state of tenability.
§ 3. The Theory of Selection.