However, it is certain problems which constitute the higher branches of ethnology; and it is to the investigation of these that the department of ethnological dynamics is subservient. Looking backwards we find, first amongst the foremost, the grand questions as to—

The unity or non-unity of the human species has been contemplated under a great multiplicity of aspects; some involving the fact itself, some the meaning of the term species.

Such are the chief views which are current amongst learned men on this point; though they have not been exhibited in a strictly logical form, inasmuch as differences of opinion as to the meaning of the term species have been given in the same list with differences of opinion as to the fact of our unity or non-unity.

These differences of opinion are not limited to mere matters of inference. The facts on which such inferences rest are by no means unanimously admitted. Some deny the constancy of certain points of structure, and more deny the permanent fecundity of mixed breeds. Again, the evidence of language applies only to known tongues; whilst the fourth view is based upon a logical rather than a zoological view of species.

The doctrine of a multiplicity of protoplasts is common. Many zoologists hold it, and they have of course zoological reasons for doing so. Others hold it upon grounds of a very different description—grounds which rest upon the assumption of a final cause. Man is a social animal. Let the import of this be ever so little exaggerated. The term is a correlative one. The wife is not enough to the husband; the pair requires its pair for society’s sake. Hence, if man be not formed to live alone now, he was not formed alone at first. To be born a member of society, there must be associates. This is the teleological[9]—perhaps it may be called the theological—reason for the multiplicity of protoplasts.

Its non-inductive character subtracts something from its value.

The difficulty of drawing a line as to the magnitude of the original society subtracts more. If we admit a second pair, why not grant a village, a town, a city and its corporation? &c.

Again, this is either a primitive civilization or something very like it. Where are its traces? Nevertheless, if we grant certain assumptions in respect to the history of human civilization, the teleological doctrine of the multiplicity of protoplasts is difficult to refute.