The systematic assessment of claims to knowledge is the central task of epistemology. According to naturalistic epistemologists, this task cannot be well performed unless proper attention is paid to the place of the knowing subject in nature. All philosophers who can appropriately be called "naturalistic epistemologists' subscribe to two theses: (a) human beings, including their cognitive faculties, are entities in nature, interacting with other entities studied by the natural sciences; and (b) the results of natural scientific investigations of human beings, particularly of biology and empirical psychology, are relevant and probably crucial to the epistemological enterprise.