Material Culture

It may be said that a manner of progress such as this, may account for the primary discoveries of man, and for their applica tion in simple methods and appliances, but that he must have soon got beyond this dependence upon environmental suggestion; and indeed there was a gradually increasing change in the con ditions determining the nature of his discoveries and inventions. But the change was one of scope rather than of character, and was due to the extension of his environment by the addition to it of his own accumulating knowledge and equipment. Thus, the ore of a metal was at first merely one kind of rock or stone amongst many others, but with increasing discoveries of its po tentialities, man's environment was enlarged no less than it would have been if the ore had fallen from the skies, with instructions for use. Similarly, when he discovered that he could make a new kind of weapon or tool by thrusting a blade of stone into a bend or a cleft or a hole in a stick, he opened up a new field of invention, which had previously been outside his environment. Certain discoveries and inventions contained great possibilities, others had their chief value in their immediate utility, and were destined to advance but little. The pestle and mortar are much as they have always been, except in diversity of material, but the pick or the hoe led to the modern plough, and the canoe now figures as a battle-ship. In all the developments, each step has depended upon its predecessors, except in cases in which an appliance or method has reached its highest level only to be su pergeded by a rival which had evolved along different lines, and which contained greater potentialities. Thus, the spear-thrower gave place to the bow, and this to the gun, the push-quern to the rotary quern, stone-working to metal-working, though where the newer knowledge never penetrated, or met with opposition, the older ways survived.

Method of Variation.

If we take a closer view of the man ner in which inventions develop, we find that two chief factors can be distinguished. In the one case, there is the method of variation, in which the individual changes are small in amount and unimportant in their effects, or, if not so small, they are such as could have been produced by the summation of a number of such changes. It is obvious that form and size may easily change as the result of the selection of variations, whether the selection is made with a clear consciousness of possibilities or not. By variation the bronze dagger was lengthened to become a sword, the flanged celt became a palstave, and such artefacts as wooden clubs, stone celts and arrow-heads, pots and a multi tude of others developed into a variety of forms without the intervention of what is often called the inventive faculty, though not necessarily without imitation coming into play.

Mutations.

In addition to these variational changes, there are others which can only occur each as a single step of a decisive character. There can be no true intermediate stages, no summa tion of series, for example, between the worked stone held in the hand, and one fixed in a wooden haft ; between the spear with a fixed point, and a harpoon with a detaching point ; between a plain bow and a crossbow ; between a simple wooden drill and a bow-drill. In all these cases the second appliance arose by an abrupt change, of an inventive character, and we may borrow a biological term and speak of such steps as mutations.

Two kinds of mutations may be distinguished. On the one hand there are improvements made as a result of discoveries arising during the manufacture or utilization of the artefact itself. These we may call free-mutations, and they are strictly com parable with the applied discoveries of the potentialities of natural objects. If we assume that the harpoon arose from a

spear which had a bone point or blade tied to the shaft, we may regard the occasional breaking away of the point as the deter mining accident in the evolution of the new appliance. The tying cord might easily retain its connection with the shaft and be come entangled with the point, in such a way that the essential feature of the harpoon presented itself ready-made. The obser vation that there were certain advantages in this looser mode of attachment might lead to its permanent adoption for spearing fish or aquatic mammals, and the free-mutation established itself. It is not possible to do more than speculate as to the mode of ori gin of most ancient inventions. In this case, as no doubt in many others, accident may well have played the predominant part.

It is in the second kind of mutations, which may be called cross mutations, that the inventive faculty has its main opportunity. Here not only is the end pre-conceived, but a possible means is foreseen. Most modern inventions (the single steps, not com plexes such as aeroplanes and loud-speakers) are cross-muta tions, and they involve the adaptational transfer of a device or feature from one appliance to another, or the application of a device or feature that has become well-known through its utiliza tion in other artefacts. The more highly developed the state of material culture, the more numerous are the opportunities for cross-mutation, though progress is still made step by step. Early man, and even early civilized man, had relatively few such oppor tunities, but occasionally he hit upon a new method or device that contained extensive possibilities of transfer and adaptation. The idea of hafting, and the several methods of hafting (by means of lashings, tangs, sockets, etc.) were in origin based on free-mutation and variation ; but they could be transferred as cross-mutations. Similarly, devices for utilizing and controlling rotary motion were capable of transfer. We must suppose that such transfer only took place to an artefact which had reached a stage of develop ment at which the application of the mutation was a more or less obvious step to take; nevertheless it is clear that in cross-muta tion there was a greater foresight and awareness than in the of free-mutation, which only involved an appreciation of the im mediate possibilities of a chance discovery. A free-mutation is a new discovery directly applied to the construction or improve ment of an artefact, whilst a cross-mutation is the result of the extension of the utility of a known device. Any true inventive step is a mutation, and the term may be restricted in its use to the evolution of artefacts.

This "opportunist" view of the manner in which man's methods and artefacts have been evolved, emphasizes the extreme gradu alness of the process. The simplest tool and method that are based on the most superficial phenomena, may have been arrived at over and over again. Such knowledge was probably part of the equipment of Homo sapiens at the time of his first dispersal. It is evident that the greater the number of determining variations and mutations involved, the less probable is it that the same result will have been reached independently in different parts of the world. The fact that in modern times two investigators occa sionally make the same discovery or invent a similar device, has no bearing upon the question, since they work in reality in collabo ration, starting from the same point, using similar apparatus, and drawing upon the records of the same predecessors. A con sideration of modern inventive progress, in spite of its directional aims, strongly supports the opportunist view of the development of material culture.