More Is Not Always Better: The Benefits of Cognitive Limits

Some of us ordinary mortals achieve extraordinary intellectual feats. For instance, theancient Mithridates the Great (king of Pontus, a long and narrow strip of land on thesouthern coast of the Black Sea) is said to have learnt 22 languages, and to have been ablein the days of his greatest power to transact business with the deputies of every tribe subjectto his rule in their own peculiar dialect. Napoleon is known to have dictated 102 letters tosuccessive teams of perspiring secretaries almost without pause, as he prepared the finaldetails for the launching of his devastating campaign against Prussia (Chandler, 1997).One of the most celebrated physicists of our time was Richard Feynman, who won the1965 Nobel Prize in physics for his many contributions to his field, especially for his workon quantum electrodynamics. Beyond being a brilliant thinker, on the bongos Feynmansupposedly could play 10 beats with one hand against 11 with the other (Feynman, 1999;try it—you may decide that quantum electrodynamics is easier).Despite numerous examples of people with prodigious abilities that we might otherwisehave thought impossible, much of cognitive psychology rests on the premise that humaninformation-processing capacity is rather severely bounded. In the words of Kahneman,Slovic and Tversky (1982), “cognitive psychology is concerned with internal processes,mental limitations, and the way in which the processes are shaped by the limitations”(p. xii). According to Cowan (2001), “one of the central contributions of cognitive psychol-ogy has been to explore limitations in the human capacity to store and process informa-tion” (p. 2). The list of documented limitations is long and includes the now classic thesis