will become increasingly difficult to trace the connection between any given change in technological detail and the fortunes of any given obscure member of the community. But it is at least safe to say that an increase in the volume and complexity of the body of technological knowledge and practice does not progressively emancipate the life and work of the individual from its dominion. The complement of technological knowledge so held, used, and transmitted in the life of the community is, of course, made up out of the experience of individuals. Experience, experimentation, habit, knowledge, initiative, are phenomena of individual life, and it is necessarily from this source that the community's common stock is all derived. The possibility of its growth lies in the feasibility of accumulating knowledge gained by individual experience and initiative, and therefore it lies in the feasibility of one individual's learning from the experience of another. But the initiative and technological enterprise of individuals, such, _e.g._, as shows itself in inventions and discoveries of more and better ways and means, proceeds on and enlarges the accumulated wisdom of the past. Individual initiative has no chance except on the ground afforded by the common stock, and the achievements of such initiative are of no effect except as accretions to the common stock. And the invention or discovery so achieved always embodies so much of what is already given that the creative contribution of the inventor or discoverer is trivial by comparison. In any known phase of culture this common stock of intangible, technological equipment is relatively large and complex,--_i.e._, relatively to the capacity of any individual member to create or to use it; and the history of its growth and use is the history of the development of material civilisation. It is a knowledge of ways and means, and is embodied in the material contrivances and processes by means of which the members of the community make their living. Only by such means does technological efficiency go into effect. These "material contrivances" ("capital goods," material equipment) are such things as tools, vessels, vehicles, raw materials, buildings, ditches, and the like, including the land in use; but they include also, and through the greater part of the early development chiefly, the useful minerals, plants, and animals. To say that these minerals, plants, and animals are useful--in other words, that they are economic goods--means that they have been brought within the sweep of the community's knowledge of ways and means.