Subjects’ poor performance relative to normative standards on reasoning tasks has
been supposed to have ‘bleak implications for rationality’ (Nisbett & Borgida, 1975).
More recent experimental work suggests that considerations of relevance underlie
performance in at least some reasoning paradigms (Sperber et al., 1995; Girotto et al.,
2001; Van der Henst et al., 2002). It is argued here that this finding has positive
implications for human rationality since the relevance theoretic comprehension
procedure is computationally efficient and well-adapted to the ostensive
communicative environment: it is a good example of bounded and adaptive rationality
in Gigerenzer’s terms (Gigerenzer and Todd, 1999), and, uniquely, it is a fast and
frugal satisficing heuristic which seeks optimal solutions.