A controversy among economists and others interested in the limits of rational choice analysis, still running after an onset at least two decades ago, concerns whether intelligent people, and especially experts, can be subject to cognitive illusions. This note provides a striking illustration...

The paper gives an account of several well-known cognitive illusions in terms of contextual defaults which guide intuition where familiar cues are ambiguous. When the default is inappropriate, as it sometimes must be, the result is a cognitive illusion. In contrast to Kahneman & Tversky...