Open Book

System One Meets System Two

Daniel Kahneman Expands Our Vision

Magazine Issue
May/June 2012
Open Book, May/June 2012

Slow down; you think too fast. That could be the take-home mantra of the distinguished psychologist and Nobel Prize–winner Daniel Kahneman’s brilliant and eminently approachable new book, Thinking, Fast and Slow. But to reduce it merely to that wouldn’t be to take the full measure of the intricacies of his—or, for that matter, our own—thinking.

Kahneman and his longtime research partner Amos Tversky (who died in 1996) are widely credited with founding the field of behavioral economics, which uses the psychology of cognition to pin down the reasons behind the frequently irrational, and seemingly inexplicable, behavior of consumers and investors. Kahneman’s and Tversky’s research informed Malcolm Gladwell’s bestseller Blink, and inspired the many books about intuitive thinking that appeared in its wake. (See, for instance, my review from January 2011, “Misstating the Obvious: The Pitfalls of Doing What Comes Naturally.”) But where those other books focused primarily on the cognitive errors, false assumptions, illusions, and distortions that an overreliance on intuition can lead to, Kahneman, in Thinking, Fast And Slow, provides nothing less than a comprehensive dissection of the reasoning mind as a whole.

Kahneman posits that there are two systems—one faster than the other, as the title suggests—that comprise the way we make decisions both small and large, choose one product (or career, for that matter) over another, judge a neighbor trustworthy or flag him as a phony. To make clear the distinction between the two types of thinking, he suggests that we imagine each system as a separate fictional character. Even better, think of these two characters as voices that argue back and forth inside our heads, tugging us one way with unreasoned passion and tugging us the other way with dispassionate analysis.

The first system, which Kahneman, for simplicity, calls “System One,” is like a quick-on-the-draw cowboy: fast, emotional, intuitive, automatic. The second system, which Kahneman calls “System Two,” is reminiscent of a laidback sidekick—a slow, logical deliberator, content to stay in the background until called upon to weigh decisions judiciously and do the analytical heavy lifting that’ll keep impulsive choices in check. We count on these two systems of thinking to interact smoothly, but, like most characters (and systems), they aren’t entirely dependable. System One tends to take control and speed ahead, while System Two—which generally prefers to expend no more energy and extend no more effort than absolutely necessary—can be left behind in the dust, unless we consciously put on the brakes and decelerate.

On an evolutionary basis, this type of mental hardwiring set us up nicely for quick reaction times in the interest of survival. (At the first unfriendly sound in the forest, start running and keep on going, without a backward glance or second thought.) Because paying attention uses up calories, being slower and more selective in switching to concentration mode was a good way to preserve our internal energy stores when food was in short supply. But in the contemporary era, our human propensity to think fast first, in haste, only to think slow later, with regret, has made us likelier to blunder into traps—witness the long list of financial bubbles, harmful-to-your-health diet fads, and so on—whose warning signals we miss as we rush by—right into trouble.

The bottom line, alas, is that “Laziness is built deep into our nature,” writes Kahneman. Yet we need to find ways to keep on our cognitive toes. Rather than making us feel like dunces for being such easy prey, Kahneman gives us tools for doing better (or at least, learning to try harder). For one thing, he ends each of the book’s 38 chapters with examples that place his ideas in the context of everyday life, transforming what may at first seem like abstract concepts into concrete cases.

For instance, to help us grasp the impact our availability bias (judging the frequency of an event by the ease with which instances come to mind, rather than by actual statistics) has on our unconscious thoughts and behavior, he offers, “Because of the coincidence of two planes crashing last month, she now prefers to take the train. That’s silly. The risk hasn’t really changed; it is an availability bias.” Although this may be an obvious example to a professional psychologist, this approach can be taken as a model for using the commonplace to help clients—and the rest of us—sort through and understand our distortions in thought and logic.

Similarly, it’s one thing to read about heuristics (essentially, all manner of mental shortcuts, first cousin to the word eureka) and the slippery facility with which System One can substitute easier questions for the more difficult ones that would require more serious concentration from System Two. But the glitch comes to life when we read Kahneman’s conversational snippet: “The question we face is whether this candidate can succeed. The question we seem to answer is whether she interviews well. Let’s not substitute.” The ease with which System One prompts decisions based on easily available facts or impressions points to a good lesson to remember the next time you’re faced with a hiring decision: people often redirect difficult conversations without our quite realizing it until later. It might also make us more alert to the ease with which a client, friend, or family member can sidestep an uncomfortable query.

In these and other ways, perhaps Kahneman’s chief gift to readers at all levels of psychological sophistication is to provide names—and, thus, ways to talk about, and ultimately get a better handle on—our cognitive blips. Dubbing our mental processes System One and System Two is the first step to—well, minding our mind systems. Kahneman coins the term, “What You See Is All There Is” (which he refers to with the acronym WYSIATI) to remind us to ground our decisions in facts, as opposed to trusting to System One as it leaps to often erroneous hunches or assumptions based on bias, stereotype, and our own insecurities (not to mention superstition, paranoia, and general craziness). The gut instinct of System One might be right, but touch base with System Two to do some due diligence before assuming so.

In this regard, Kahneman asks us to be particularly wary of the always-alluring cognitive sin of overconfidence: thinking we know more about, have deeper insight into, or have greater control over a situation than we do. Investors who play the stock market generally fit all three of those criteria—and, unfortunately, so do many experts and professionals in any number of fields, including psychology and psychotherapy.

Yes, expert intuition based on experience can be invaluable in some situations, Kahneman points out. The problem is that overconfident experts assume their judgments are infallible in all situations and tasks within their professional domain. But, Kahneman reminds us, that’s not necessarily—or usually—so. “Expertise is not a single skill; it is a collection of skills, and the same professional may be highly expert in some of the tasks in her domain while remaining a novice in others,” he writes. In short, expertise is specific and specialized. But the illusion of overconfidence blinds us to these limitations. Overconfidence in one’s own expert judgments can lead professionals to discount or disregard the validity of data-based formulas while overvaluing their hunches.

Kahneman is explicit about the potentially insidious impact on psychotherapists of falsely assuming that being highly skilled in one aspect of practice will carry over to all aspects. He writes: “Psychotherapists have many opportunities to observe the immediate reactions of patients to what they say. The feedback enables them to develop the intuitive skill to find the words and the tone that will calm anger, forge confidence, or focus the patient’s attention. On the other hand, therapists do not have a chance to identify which general treatment approach is most suitable for different patients. The feedback they receive from their patients’ long-term outcomes is sparse, delayed, or (usually) nonexistent, and in any case too ambiguous to support learning from experience.”

Kahneman then describes how this imbalance all too often plays out in practice: “An experienced psychotherapist knows that she is skilled in working out what is going on in her patient’s mind and that she has good intuitions about what the patient will say next. It is tempting for her to conclude that she can also anticipate how well the patient will do next year, but this conclusion is not equally justified. Short-term anticipation and long-term forecasting are different tasks, and the therapist has had adequate opportunity to learn one but not the other.”

The key to overcoming overconfidence is learning to identify and recognize the limits to our expertise. One way to do that is through gaining—and paying attention to—clear and regular feedback, as well as outside views or opinions. Another is to reexamine biases against data-driven rules or checklists in favor of our own (limited) experience. Subjective confidence and intuition may be extremely useful in coming to a judgment, but they shouldn’t be the only components on which you base predictions, howsoever expert in a field you may be.

After reading Kahneman’s opus, it seems only fair to ask: so, can we train ourselves to make better, more rational decisions, rather than fall prey to faulty choices based on emotion and intuition? The equally fair answer is: sometimes we can, but not always. It’s precisely because the human mind is a meaning-making machine that we’re so easily fooled into seeing meaning and patterns where none exist. Kahneman’s achievement is in breaking down the mechanisms by which we make meaning where there is none, as well as when there is, and see patterns when they don’t exist, as well as when they do. More than that, he shows us that the seemingly countless ways in which we can confuse the one for the other isn’t just the work of System One and System Two: it’s the product of being human.


Diane Cole

Diane Cole is the author of the memoir After Great Pain: A New Life Emerges and writes for The Wall Street Journal and many other publications.