 Finally, in Longino’s critical contextual empiricism, the cognitive processes that eventuate in scientific knowledge are themselves social (Longino 1990, 2002). Longino’s starting point is a version of the underdetermination argument: the semantic gap between statements describing data and statements expressing hypotheses or theories to be confirmed or disconfirmed by that data. This gap, created by the difference in descriptive terms used in the description of data and in the expression of hypotheses, means that evidential relations cannot be formally specified and that data cannot support one theory or hypothesis to the exclusion of all alternatives. Instead, such relations are mediated by background assumptions. Eventually, in the chain of justification, one reaches assumptions for which no evidence is available. If these are the context in which evidential relations are constituted, questions arise concerning how the acceptance of such assumptions can be legitimated. According to Longino, the only check against the arbitrary dominance of subjective (metaphysical, political, aesthetic) preference in such cases is critical interaction among the members of the scientific community or among members of different communities. There is no higher authority or transcendent aperspectival position from which it is possible to adjudicate among foundational assumptions. Longino takes the underdetermination argument to express in logical terms the point made by the sociologically oriented researchers: the individuals participating in the production of scientific knowledge are historically, geographically, and socially situated and their observations and reasoning reflect their situations. This fact does not undermine the normative enterprise of philosophy, but requires its expansion to include within its scope the social interactions within and between scientific communities. What counts as knowledge is determined by such interactions.