The Marx quote under discussion implies that ruthless criticism is a condition of science, or perhaps the social sciences in particular. Is it possible to go one step further and contend that a position of opposition to the existing social order is a necessary precondition of science? This may be the case because: 1) it is only from this kind of position that sufficiently ruthless criticism can be carried out. 2) it is only those classes and groups opposing the existing social order who have an interest in discovering rather than obsuring truth (big T). This argument can be applied to the "hard" sciences, through observing their genesis in the bourgeois struggle against the hegemony of feudal religious ideology (parenthetically the pope has recently stated that there probably is something to the theory of evolution). If accepted this argument provides a first criterion of discrimination between different contending paradigms or versions of Truth (small t). Of course not every oppositional ideology will constitute a science but even short of a scientific outlook, oppositional ideologies will have a greater chance of producing knowledge than non-oppositional ones. Terry McDonough