These developments serve as part of the background to a debate in epistemology which originated with Cherniak’s (1981; 1984; 1986) theory of minimal rationality. Cherniak attempts to provide a characterization of rationality which is responsive to both traditional normative characterizations as well as complexity theoretic results about the difficulty of deductive inference of the sort discussed above. According to his account, a minimally rational agent need only make some of the valid inferences which follow from his beliefs in a proof system for classical logic. He further suggests that the inferences which are selected may depend on the sorts of heuristics considered by cognitive psychologists such as Tversky and Kahneman (1974). As such, Cherniak proposes that the use of heuristics which may be of benefit to an agent in certain circumstances – even potentially unsound ones – should be regarded as falling under a generalized account of rationality informed by computational complexity theory. Related themes are discussed by Harman (1986) and Morton (2004; 2012).