There are facts and arguments by which this hypothesis may be raised to so high a degree of probability, that its soundness can scarcely be doubted. A single example of them must Attlee. It is the received opinion that among the advanced tribes contain ing genies, property was originally vested in the gens, and was only by slow degrees wrested from it by the family. It is involved in this, that at one time the gens was everything, the family nothing, in the organization of the tribe; that the latter grew, and that as it grew, the former sunk in importance. The tribe, when property was exclusively vested in its gentes, must have been an aggregate of gentes, not an aggre gate of families. All this is consistent with, and corroboratory of the hypothesis of development; in particular, it strongly corroborates the view that the tribe at an early period consisted of several bodies of kindred, accounted distinct from each other, and each of which held property in common. It has never been accounted for upon any other view.
The only other theory which has been formed of the origin of tribes—commonly called the patriarchal theory—is that a tribe consists in the main of the descendants of a single family, descent being chiefly, if not exclusively, reckoned through males; and that the genies found within the tribe consist of the descendants of individual sons or grandsons of the common progenitor. It is evident that this theory does not explain the organization of the numerous class of tribes first considered. It has been formed upon observation of the advanced tribes of the classical type, but it does not consist with the history of property (to test it at a single, but a vital point) even among them. It might account for property being vested in the tribe; it does not account for it vested in the geutes. It can only do so by the aid- of the assumption that, though the sons and grandsons of the original progenitor had the desire for family property, and divided his property, or accumulated property of their own, their descendants suddenly lost that desire, and began to hold in common. But such a supposition is
too improbable to he'entertained. This theory is also excluded in the case of all polyandrous peoples, for it assumes that society began with monandric marriage, a per fect idea of the family and male kinship—all conditions the very opposite of those which must at one time have prevailed among such peoples. And polyandry can be shown to have prevailed so widely, that it is probable it has been the earliest practice of every human tribe. However this may be, a theory which is contradicted by a great propor tion—much the greatest number—of the cases to be accounted for, and is in important respects not consistent with any class of cases, cannot be a good hypothesis; and there fore the patriarchal theory has no title to be accepted as explaining the normal history of the formation of tribes, or of any class of tribes. Its fundamental assumption, indeed —the segregation of individuals who became progenitors of tribes—seems to be at vari ance with the nature of man, which all experience has shown to be social and gregarious, and to be the most averse to separate and independent action, when society is the least advanced. It should also be stated that it fails to do what a sound theory of tribal forma tion must do—to account for the fusion of neighboring tribes, independently of con quest. into one people. To account for this, it has been customary to suppose that neighboring tribes, wishing to unite, adopted one another; but there is no evidence of such adoption having ever been practiced, and the supposition seems entirely improbable.
The patriarchal theory was, until recently, the received account of the formation of tribes. The theory which has here been styled the hypothesis of development was first propounded. though without elaboration, in a work published in 1865, Primitive Mar ria5e, by J. F. McLennan.