EVALUATING THEORIES

John Vasquez claims to follow Imre Lakatos but distorts his criteria f or judging theories and evaluating research programs. Vasquez claims t hat facts observed can falsify a theory by showing that its prediction s are wrong. He fails to consider the puzzles posed by the interdepend ence of theory and fact. He places all realists in a single paradigm d espite the divergent assumptions of traditional and structural realist s. In contrast to Vasquez, I argue that explanation not prediction, is the ultimate criterion of good theory, that a theory can be validated only by working back and forth between its implications and an uncert ain state of affairs that we take to be the reality against which theo ry is tested, and that the results of tests are always problematic.