The preceding article by William A. Green does not make clear the basis upon which he criticizes my October 1981 comparison of Belize and the British sugar colonies. He begins by saying that the “phenomena compared must possess important and comprehensive unities of character” and writes later that “it is the presence of similar people performing similar functions under similar circumstances that renders comparative analysis valuable. These identities did not prevail between Belize and the British sugar colonies.” Belize, he writes, had a “unique system of domination” (his emphasis). Is the problem, then, that there are no “unities of character,” that “identities did not prevail,” or that Belize was “unique”? Every case is unique, surely, yet comparisons are made in social, as in natural, science between selected common factors which appear under similar, but not identical, conditions. There exists a range between John Stuart Mill's formulae called The Method of Agreement, in which one compares two situations which differ in every respect save one, and The Method of Difference, in which one compares two situations which are alike except in one respect, but Green seems to think only the latter is acceptable.