Since biological change occurs slowly and cultural changes occur in every generation, it is futile to try to explain the fleeting phenomena of culture by a racial constant. We can often explain them-in terms of contact with other peoples, of individual genius, of geography-but not by racial differences.

Since biological change occurs slowly and cultural changes occur in every generation, it is futile to try to explain the fleeting phenomena of culture by a racial constant. We can often explain them-in terms of contact with other peoples, of individual genius, of geography-but not by racial differences.