In the entire circuit of the globe those races which have developed under a tropical sun are found to be indolent and fickle. From the standpoint of survival of the fittest, such vices are virtues, for severe and continuous exertion under tropical conditions bring prostration and predisposition to disease. Therefore, if such races are to adopt that industrious life which is a second nature to races of the temperate zones, it is only through some form of compulsion. The negro could not possibly have found a place in American industry had he come as a free man.

pg. 136. - Races and Immigrants in America, 1907