"father," for instance, is applied to all those whom the father would call brother, and to all the husbands of those whom the mother calls sister, both brother and sister being used in a far wider sense than among ourselves. In some forms of the classificatory system the term "father" is also used for all those whom the mother would call brother, and for all the husbands of those whom the father would call sister, and in other systems the application of the term may be still more extensive. Similarly, the term used for the wife may be applied to all those whom the wife would call sister and to the wives of all those whom the speaker calls brother, brother and sister again being used in a far wider sense than in our own language.
The classificatory system has many other features which mark it off more or less sharply from our own mode of denoting relationship, but I do not think it would be profitable to attempt a full description at this stage of our enquiry. As I have said, the object of these lectures is to show how the various features of the classificatory system have arisen out of, and can therefore be explained historically by, social facts. If you are not already acquainted with these features, you will learn to know them the more easily if at the same time you learn how they have come into existence.
I will begin with a brief history of the subject. So long as it was supposed that all the peoples of the world denoted relationship in the same way, namely, that which is customary among ourselves,
