ABSTRACT: Decision-theoretic approach and a nonlinguistic theory of norms are applied in the paper in an attempt to explain the nature of scientific rationality. It is considered as a normative system accepted by scientific community. When we say that a certain action is rational, we express a speaker’s acceptance of some norms concerning a definite action. Scientists can choose according to epistemic utility or other rules and values, which themselves have a variable nature. Rationality can be identified with a decision (...) to accept a norm. This type of decision cannot be reduced only to its linguistic formulation; it is an act of evolvement of the normative regulation of human behavior. Norms are treated as decisions of a normative authority: a specific scientific community is the normative authority in science. These norms form a system and they are absolutely objective in the context of individual scientists. There exists an invariant core in all the norms of rationality, accounting for their not being liable to change, as compared with the flexibility of legal norms. The acceptance of and abidance by these norms is of social importance – it affects the aims of the community. A norm only defines the common framework and principles of scientific problem-solving; its application is a matter of professional skills and creative approach to a particular problem. It is of no importance at all, if an agent’s cognitive abilities do not live up to the requirements of a norm. Such discrepancy can be compensated for by the fact that a scientist carries out work in a conceptual and normative framework established by a respective scientific community. (shrink)