Cognitive values are the characteristics that are constitutive of good theories, the criteria to which we appeal when choosing among competing theories. I argue that, in order to count as a cognitive value, a characteristic must be needed to explain actually made theory choices, and its cognitive significance must be well defended especially in view of considerations derived from the objective of science. A number of proposed objectives of science are entertained, and it is argued that adopting a par-ticular objective (...) is dialectically intertwined with commitment to certain social values.Then, the ways in which science is, and is not value free is explored briefly, leading to the identification of a level of analysis where values may influence theory choice without causing paradox or threatening the impartiality of soundly-made scientific judgments. (shrink)