I would sum up these reflections on the relations of the individual and the group by the practical deduction that to understand the individual we must study him in relation to the group, and to understand the group we must study it, primarily in the individuals of which it is composed, in both their physical and mental life; and secondly, in those principles and processes which it, as an entirely psychical product, presents peculiar to itself. The group is _not_ a “natural” product in the objective sense in which that word is employed in the term “natural sciences.” It is a purely mental creation, though none the less real. It must be examined and investigated by other methods, therefore, than those customary in the biologic sciences. Instead of studying external phenomena for their own sake, we must regard all such as valuable only as they indicate psychic changes, and as they can be translated into mental correlates. The study is, therefore, from within, and qualitative rather than quantitative, in this respect contrasting with experimental psychology and also with history. When we examine in detail the interaction of the individual and the group we may classify the processes which take place somewhat as follows: The individual receives from the group the symbols for complex and general ideas—that is, the words of language; he is also taught many complex purposeful motions, such as are needed in social and cultured life; he is supplied with artificial objects for his use, as tools, clothing, shelter, etc.; and he is constantly subjected to a certain amount of physical force from those around him—in other words, is “made to do” a variety of acts. The group may consciously strive to modify him, as in public education, religious instruction, and the like; or it may act merely negatively in opposing any developments antagonistic to its own character. The individual may work for or against the group, or for himself only; but in either case has to reckon with the group for what he obtains from it. While the _unity_ of the ethnic mind is fostered by a conscious effort to promote common interests, modes of expression, ambitions, and aims, its energy is in direct proportion to the cultivation of the sense of individuality among its members, for from the latter alone are born the impulses to progress. The fatal error of many communities has been to bend every effort to secure the former, while they neglected or actually endeavoured to suppress the latter. I have been using the word “group” in a loose way. The time has now come to distinguish it from various other terms familiar to ethnology, such as tribe, folk, nation, people, stock, and race. “Group” is the best English equivalent for the Greek _ethnos_, which word, by its derivation, means a number of people united together by habits and usages in common.