This has occurred particularly in regard to language and racial types. Indeed, the opinion is still held by some investigators that linguistic relationships and racial relationships are in a way interchangeable terms. An example illustrating this point of view may be seen in the long-continued discussions of the home of the “Aryan race,” in which the blond northwest European type is identified with the ancient people among whom the Indo-European or Aryan languages developed. If it could be shown that distinct languages belong to distinct racial types, and that these languages exhibit different levels of development or indicate different types of thought, we should have gained a sound basis which would allow us to discuss the genius of each people as reflected in its language. If, furthermore, we could show that certain cultural types belong to certain races and are foreign to the genius of others, our conclusions would be founded on much firmer ground. Thus we are led to a consideration of the all-important question whether types, languages, and cultures are so intimately connected that each human race is characterized by a certain combination of physical type, language, and culture. It is obvious, that, if this correlation should exist in a strict sense, attempts to classify mankind from any one of the three points of view would necessarily lead to the same results; in other words, each point of view could be used independently or in combination with the other ones, to study the relations between the different groups of mankind. As a matter of fact, attempts of this kind have often been made. A number of classifications of the races of man are based wholly on anatomical characteristics, yet often combined with geographical considerations; others are based on the discussion of a combination of anatomical and cultural traits which are considered as characteristic of certain groups of mankind; while still others are based primarily on the study of the languages spoken by people representing a certain anatomical type.