The relation of cause and effect, as commonly conceived by the vulgar and as commonly employed by the scientist, is a putative relation between phenomena which can not be said to stand in any observed relation of efficiency to one another. Efficiency, as understood in this connection, is not a fact of observation, but of imputation; and efficiency, performance of work, is the substance of the causal relation as that concept is universally employed in modern science. It may well be said that this recourse to the concept of efficient cause--a metaphysical postulate touching a putative fact--is the distinguishing characteristic of modern science as contrasted with any other scheme of systematised knowledge.[130] Not only does the development of modern science rest on this postulate of causality, but the concept of causation which so characterises the modern sciences is of a particular and restricted kind. At least on the face of things it seems unquestionable that the peculiar temper and limitations of this modern European concept of causation are to be credited to the habits wrought out by a life under the handicraft system. It has been noted already that the ubiquitous prevalence of trade and of the price system in modern times has given to the modern apprehension of facts a certain objectivity, a degree of impersonality, which is at least a characteristic of modern knowledge, whether scientific or commonplace, even if it cannot be said to be a unique distinction of modern science as contrasted with other deliberate systems of knowledge. But it is the unique distinction of modern science, particularly as it comes into view in its early phases, that its concept of causality is drawn not simply in terms of workmanship but specifically in terms of craftsmanship. There need probably be no argument spent on the thesis that the sense of causality is, by and large, a particular manifestation of the sense of workmanship. But the sense of workmanship in its native scope apparently covers something more than the manual efficiency of the skilled workman simply. And in other times and under other cultural (technological) circumstances the sense of workmanship has apparently given rise to concepts of causation of a wider, or at least of a looser, scope. In the naïve rating of savage peoples workmanship appears to cover, perhaps uncertainly, notions of generation, nurture, tendance, and the like, without any sharp line being drawn between these various lines of effective endeavour on the one side and manual efficiency on the other. And so, on the other hand, in the cosmological knowledge (or quasi-knowledge) current among these peoples explanation in terms of generation and growth are accepted as final along with explanations in terms of what the modern man would conceive to be the stricter sense of cause and effect. Even in the speculations of the sages of classical antiquity, and again in the cosmologies and natural