Reader Comments about

What Intelligence Tests Miss:  The Psychology of Rational Thought

“In this compellingly readable book Keith Stanovich explains the bold claim that the notions of rationality and intelligence must be distinguished sharply and studied separately. His proposal would deeply change both the field of intelligence testing and the study of individual decision making-and he may well succeed.”

— Daniel Kahneman, Princeton University, Nobel Laureate in Economics

“Despite a long tradition of research in both fields, the psychological study of

intelligence and its tests has not been well integrated with the psychological study of rationality.  Keith Stanovich’s well-written and accessible book does integrate these studies and should, for that reason alone, have a highly beneficial impact on both.  Stanovich argues that standard intelligence tests miss the trait than can be of even greater value than relatively high intelligence: rationality.”

— review in Trends in Cognitive Sciences Over_Dysrationalia_Review_TICS_2010.pdf

Bond, M. (October 31, 2009).  Clever fools: What good are smarts if you don’t know how to use them.  New Scientist, 204(2732), 36-39.


“Stanovich makes a compelling argument that we need to put more emphasis on measuring and teaching critical thinking skills. His clear writing and his many interesting examples make the book accessible and engaging. What Intelligence Tests Miss illuminates the actions of everyone who affects our lives, from our family members to our co-workers to President Bush.”

— Nicole Branan, Scientific American MIND

Review in Scientific American MIND

“Stanovich warns that as long as we continue to worship IQ tests that do not assess rational thought processes, we will continue to misjudge our own and others' cognitive abilities”

— Kacie Glenn, Chronicle of Higher Education, January 30, 2009

review in the Chronicle:  Chron_Higher_Ed.pdf

“In this dazzling synthesis about how well and poorly people think and why, Keith Stanovich drives a wedge between intelligence and rationality. This book demonstrates compellingly how rationality is more than intelligence and how those who are intelligent can be dismayingly irrational.”

— David Perkins, Harvard University, author of The Eureka Effect

“In this smart and rational book, Keith Stanovich explains the difference between intelligence and rationality. Stanovich, one of psychology’s wisest writers about intelligence, also shows that IQ tests do not measure the full scope of mental ability because they fail to assess rational thought, which is central to happiness and fulfillment.  This book is essential reading for anyone who wants to know what makes us truly smart—and why smart people often behave irrationally.”

— Carol Tavris, coauthor of Mistakes Were Made (But Not by Me)

"Professor Stanovich has an unparalleled ability to synthesize results from diverse domains of cognitive science in a lively way that is tremendously useful to us non-specialists. This book is not about emotional or multiple intelligence; it's about intelligence in its most important practical dimensions."

— E. D. Hirsch, Jr., author of The Knowledge Deficit and The Schools We Need

“We all know what Keith Stanovich is talking about in this book, and we all have our anecdotal examples—people with high IQs often do very stupid things.  Stanovich thinks he can tell us why, and goes a long way towards doing so. Using evocative language he demonstrates, using vivid examples, how lazily we often use our minds and what this apathy costs us. He also shows how the way we test for educational potential and teach even those we deem most educable has not kept up with our modern probabilistic and relativistic world.  Anyone interested in human intelligence and how we assess its individual differences should pay close attention to what he says, which is that intelligence tests don't measure rationality.”

— Wendy Johnson, Times Higher Education Book of the Week

review link

“This is an important but also controversial book, controversial inasmuch as it radically challenges received wisdom…. It is written with admirable clarity and enriched by numerous real-life examples of inadequate reasoning.  Except perhaps for the models and technical passages on Bayes' theorem, the work is quite accessible for the curious and open-minded (I dare not say ‘intelligent’) lay person. It cannot be too strongly recommended, and given the prominence of IQ testing in our culture, deserves the widest possible readership.”

— Gustav Jahoda, review in Metapsychology

review link

“In his new book, psychologist Keith Stanovich offers a way to understand the difference between intelligence and common sense.  As the book title suggests, Stanovich argues that our conception of ntelligence is incomplete….Stanovich points out that we do very little in schools to nurture the reflective mind. Given that it is important to reaching ones goals, academic or otherwise, perhaps we should.  Steve Pinker has suggested that schooling should especially focus on cognitive processes that we deem important, but that the mind does not do well naturally. By that criterion, the reflective mind qualifies for more attention in schools because quite a lot of data show that most of us do not use the it as optimally as we might.”

— Dan Willingham, review in Encyclopedia Britannica Blog

review link

"In this brilliant and entertaining book, Keith Stanovich shows that intelligence tests, though they have their uses, fail to assess the key components of rational thought and action."

— Philip Johnson-Laird, Princeton University, author of How We Reason

Keith Stanovich has written a brilliant book. But it’s not this one.  His brilliant book is How to Think Straight About Psychology, now in its ninth edition. It is probably the best book about rational thinking in psychology (and elsewhere) I have ever read…..This new book by Stanovich is also good. It has a lot of interesting material about rational thinking and how it is important in human life.  Along the way there are very nice and novel examples and illustrations of rational thinking, and how badly supposedly intelligent people do in this field…..The writing is very good; somewhere between a cognitive psychology textbook and Freakonomics.  The book does a good job of showing that rationality is important; it also, to something of a lesser extent, shows that rationality is not always strongly associated with conventionally measured intelligence.  —  Ian Deary, The Psychologist  Deary_Review.pdf

This is an important book for much the same reason that Daniel Goleman's best-selling Emotional Intelligence has proven so useful: it is based on sound evidence and allows for better prediction and education for success.  This engaging and accessible book is highly recommended for most public and academic libraries. 

Library Journal

Why Smart People Do Stupid Things

University of Toronto Magazine    Link

“We’re natural-born ‘cognitive misers’—creatures of an evolution that has shaped us to seek rapid, instinctive “ballpark answers” rather than expend the mental energy required for exact solutions. What fascinates Stanovich, and makes his book, What Intelligence Tests Miss (Yale UP), both entertaining and scientifically significant, is that cognitive parsimony—and a host of other barriers to rational thought—are no respecters of IQ. The highly intelligent are as prone to irrationality as anyone else, and there is no reason to be surprised when smart people do dumb things.”

— Brian Bethune,  Macleans (Canada)


“Stanovich’s book shows what might be accomplished if schools, businesses, and government focused on what intelligence tests miss”

— Kendrick Frazier,  Skeptical Inquirer, March/April, 2009

Stanovich believes that the concept of intelligence, as measured by IQ tests, fails to capture key aspects of mental ability.

— George Dvorsky, Institute for Ethics and Emerging Technologies


"An original, well-supported, and brilliantly tied together book that reveals the misunderstood relationship between IQ, intelligence, and rationality."-

— David Over, Psychology Department, Durham University