invention, however, remains such regardless of its fate at the hands of social selection. Yet we must consider several possibilities since it is conceivable that the environment might be the determining factor in the selection alone, leaving the individual free to invent as he choose. Hence, our discussion falls under two heads: (a) The relation of the environment to invention; (b) to the selection, or socialization of inventions.
One of the fundamental problems in the investigation of invention has been the determination of what the process really is. It is in a way a creative process, but it must have something to work upon; it can not make something of nothing. We need not, however, distress ourselves with the puzzle as to whether there can ever be a distinctly new idea, for an invention in the cultural sense is a new relation assumed or observed between old experiences rather than an experience itself. When the geographers claim that all concrete experiences involved in such an invention must come from the environment, they are on indisputable ground. Thus it is undoubtedly due to the presence of snow that the Eskimo invented the snow house and to experience with birchbark that the Eastern Woodland Indians devised the bark-covered tipi. The real problem is as to whether there is anything in the very nature of birchbark as a part of the environment that necessitates the invention of a certain peculiar kind of house. Unless one holds to an ancient belief, he must assuredly say that there is no such necessity. It is true that a person who never experienced birchbark directly or by hearsay could not have made the invention, and if he had, it could not have passed into practise unless the material was made available by the environment. Thus it is clear that the environment furnishes the materials from which inventions are made and which thereby enter into the so-called material cultures of peoples. But the essential thing in an invention is the relation between experiences. In the case of birchbark the relation between bark experience and house-building experience can have no existence outside of the psychic life of man, the environment can lay no claim to it. Its production must emanate from the human mind and not from the earth. It seems, therefore, that we have here an answer to our query, for by the nature of the inventive process the determining factor is found in mental activity. Environment furnishes the materials and in that sense only limits invention. To invent a birchbark-covered house a man must have lived among birch trees, but the mere living there does not require such an invention.
We have noted that an invention becomes a cultural trait when taken up by many individuals. In this case the relation is handed on and on by education and imitation and so cultural traits are after all based upon a recognized relation between experiences. The causes that lead to the adoption or rejection of an invention must be recognized as the
