There are at least two reasons for United States and Latin American historians to bring their work together in a comparative thesis, the first being the need to maximize control of generalizations, and the second being the need to write the history of the social process by which a single world community has been developing since the sixteenth century. Recently, considerable progress with the first task has been made in the study of slavery and race relations, but little progress can yet be reported with the second.
One result of the work on slavery and race relations ought to warn and encourage us. Without entering here into a discussion of the specific points of view advanced by Frank Tannenbaum, Marvin Harris, Sidney Mintz, Stanley Elkins, Gilberto Freyre, Herbert Klein, and so many others, it could be demonstrated that the comparisons of slavery in the United States, South America, and the Caribbean have so far proven enormously important in clarifying issues and stimulating new research and yet have failed to yield some of the most sought-after generalizations.