In 1888, he declared that "the development of ethnology is largely due to the general recognition of the principle of biological evolution"; since Boas's times, physical anthropologists have established that the human capacity for culture is a product of human evolution.
在1888年，他宣称“民族学的发展大部分歸功於對生物演化原则的普遍认定”；從鲍亚士的时代以來，体质人类学家已确立，人类的文化能力是人类演化的产物。