words. The task is extremely difficult when the colored words are
themselves names of color (e.g., GREEN printed in red, followed by Y
ELLOW printed in green, etc.).
psychopathic charm : Professor Hare wrote me to say, “Your teacher was
right,” March 16, 2011. Robert D. Hare, Without Conscience : The
Disturbing World of the Psychopaths Among Us (New York: Guilford
Press, 1999). Paul Babiak and Robert D. Hare, Snakes in Suits : When
Psychopaths Go to Work (New York: Harper, 2007).
little people : Agents within the mind are called homunculi and are (quite
properly) objects of professional derision.
space in your working memory : Alan D. Baddeley, “Working Memory:
Looking Back and Looking Forward,” Nature Reviews: Neuroscience 4
(2003): 829–38. Alan D. Baddeley, Your Memory: A User’s Guide (New
York: Firefly Books, 2004).

2: Attention and Effort

Attention and Effort : Much of the material of this chapter draws on my
Attention and Effort (1973). It is available for free download on my website
(www.princeton.edu/~kahneman/docs/attention_and_effort/Attention_hi_quality.pdf).
The main theme of that book is the idea of a limited ability to pay attention
and exert mental effort. Attention and effort were considered general
resources that could be used to support many mental tasks. The idea of
general capacity is controversial, but it has been extended by other
psychologists and neuroscientists, who found support for it in brain
research. See Marcel A. Just and Patricia A. Carpenter, “A Capacity
Theory of Comprehension: Individual Differences in Working Memory,”
Psychological Review 99 (1992): 122–49; Marcel A. Just et al.,
“Neuroindices of Cognitive Workload: Neuroimaging, Pupillometric and
Event-Related Potential Studies of Brain Work,” Theoretical Issues in
Ergonomics Science 4 (2003): 56–88. There is also growing experimental
evidence for general-purpose resources of attention, as in Evie Vergauwe
et al., “Do Mental Processes Share a Domain-General Resource?”
Psychological Science 21 (2010): 384–90. There is imaging evidence
that the mere anticipation of a high-effort task mobilizes activity in many
areas of the brain, relative to a low-effort task of the same kind. Carsten N.
Boehler et al., “Task-Load-Dependent Activation of Dopaminergic
Midbrain Areas in the Absence of Reward,” Journal of Neuroscience 31
(2011): 4955–61.
pupil of the eye : Eckhard H. Hess, “Attitude and Pupil Size,” Scientific