First of all, it is obvious that spatial extension must not be measured mechanically. To work on the assumption that a custom or art practised over a million square miles was a third as old again as one practised over seven hundred and fifty thousand, would be too often contrary to the evidence of known history as well as the dictates of reason. Culture traits do die out, from inanition, from sterility of social soil, through supplanting by more vigorous descendants. Continuity is therefore not a necessary ingredient of geographical range. An ancient trait may have been displaced in all but a few remote peripheral tracts. The areas of these may aggregate but little. Yet the distances between them are likely to remain greater than the longest range of a later trait which has replaced the earlier one over most of its original territory.
Thus, alphabetic writing is more recent than the ideographic and rebus methods, but in the year 1500 A.D. was in use over a larger area in Europe, Africa, and Asia than the surviving Chinese and Mexican systems occupied. Yet these two outlying systems enclosed between them a larger tract than those over which the alphabets had diffused.
So, at the same period, was agriculture practised by peoples holding more area than was occupied by non-agricultural ones. But the former constituted two great and continuous groups, one in each hemisphere, to which the non-agricultural peoples in the north of Asia, the south of Africa, the remote continent of Australia, the north of North America, and the south of South America were obviously peripheral. Agriculture being of necessity later than the non-agricultural state, and there being thus no doubt that the marginal hunting peoples represent the remnant of a condition that was once world-wide, it appears that there must be a presumption of validity in favor of reckoning the extent of a scattered custom by its included rather than its actual area.
Of course, the situation is not always so simple. There may exist the possibility of two or more marginal areas sharing a trait as the result of parallelism. Half-hitch basketry coiling in Tasmania and at Cape Horn might logically be the last survival of a very ancient world-wide diffusion, or the product of two thoroughly independent inventions, or of parallel processes of degeneration in isolated and culturally unstimulated nooks. The last two interpretations in fact seem more conservative than the first. If half-hitch coiling were as antecedent in its nature to other coiling and to weaving as wild foods are to cultivated ones; or if the Old Stone Age remains showed it to have been actually so; or if it were practised by a considerable number of tribes in four or five rather large marginal areas instead of two quite narrow ones, diffusion, and the consequent antiquity of the trait, could be inferred with high probability. In short, the periphery argument must not be stretched too thin.
Obviously, too, comparables must be compared: coiling with twining, hand-weaving with loom-weaving; not, however, the very special variety of half-hitch coiling with the entire array of weaving techniques. Nor would it be fair to balance the whole group of true alphabets in the year 500 B.C. against the particular rebus system of Egyptian hieroglyphs from which they were possibly derived but which they had already much exceeded in their diffusion. Yet the distribution of all alphabets as against that of all ideographic and rebus systems would lead, at that date as two thousand years later, to the same interpretation that the facts of history actually give.
171. Cultural Ranking
Consideration must also be allowed, within certain limits, to cultural superiority and inferiority. This is a criterion that has been abused in the earlier anthropology, but it is usable with caution, especially where a measure of experience confirms the grading that seems rational. A machine process would normally be later than a manual one: cloth, for instance, subsequent to basketry. The antiquity of both these products happens to be so great that little or no direct historical evidence exists, and their perishability precludes much help from archæology. Yet there is this indirect evidence: there are peoples that make baskets only, others that make baskets and cloth, none that make cloth only. Cloth thus is something superadded, which, not coming into competition of utility with basketry, coexists with it.
Where two devices serve the same end and come into full contact, the issue is even simpler, because the better crowds out the worse. There is no record of any people, once able to produce metal axes or knives, reverting to or inventing stone ones. An adequate system of recording events has always maintained itself. Literacy may have become less frequent, now and then, under economic or military stress, and literature poorer, but no recording culture has ever gone back wholly to oral tradition. Specific systems of records have indeed died out—witness Egyptian and Cuneiform: but only because they were rendered useless by more efficient systems of pure phonetic writing. These, on the other hand, have never been known to yield to non-phonetic systems.
It is very different with culture phenomena whose ranking is based solely on the operation of our imaginations. In such cases judgment should if possible be wholly suspended until evidence is available. For fifty or sixty years it has seemed eminently plausible and natural, even inevitable to most people, that matrilinear institutions preceded patrilinear ones, because a man must know his mother, but in a condition of promiscuity would not know his father. Yet incontrovertible historical evidence of a change is conspicuously deficient, so that the belief in the antecedence of the matrilineate has remained founded solely in hypothesis. As has been indicated above (§ [110]) and will be shown more in detail below (§ [185]), the indirect evidence of distribution indicates rather that definitely matrilinear and patrilinear institutions have tended to be closely associated, and that among exogamous and totemic peoples the matrilineate has usually been the later phase.
In fact, one important stimulus to belief in matrilineal priority has been the awareness that the most advanced cultures of the recent period have inclined to count descent from the father. But it is obviously unfounded to deduce from this that ancient and primitive nations favored mother-reckoning. It would be equally logical—or illogical—to infer that what is had always been since institutions arose, as to argue that because a thing is now it must formerly not have been.