we harbor two selves when it comes to happiness, too: one self that experiences pain and pleasure from moment to moment and another that remembers the emotions associated with complete events and episodes. The remembering self does not seem to care how long an experience was if it was getting better toward the end—so a longer colonoscopy that ended with decreasing pain will be seen later as preferable to a shorter procedure that involved less total pain but happened to end at a very painful point.

we want to buy the illusions that the marketing world sells to us—hook, line and sinker. Which may be the scariest thing of all.

There's nothing metaphorical about "gut feelings," for what happens in the gut really does influence what we feel. Nor is it just the gastrointestinal tract that alters our minds. Mr. Damasio has shown that neurological patients who are unable to detect changes in their own bodies, like an increased heart rate or sweaty palms, are also unable to make effective decisions

This research shows that the immateriality of mind is a deep illusion. Although we feel like a disembodied soul, many feelings and choices are actually shaped by the microbes in our gut and the palpitations of our heart.

We live at a time when seemingly everything is available, but it's more likely than ever before that we're all reading the same thing. The lure of conformity is hard to resist. This research reveals the downside of our hyperconnected lives

Instead of thinking for ourselves, we simply cite what's already been cited. We should be wary of such influences. The only way to preserve the wisdom of the crowd is to protect the independence of the individual.

Physical warmth activates circuits in the brain associated with feelings of psychological warmth. The insular cortex, or insula, plays a critical role in this crossover between the outside world and our experience of it. This peach-sized region helps us to perceive whether a sensation is hot or cold, pleasurable or painful. It is activated when we crave chocolate, fall in love or get disgusted. The insula also guides us on social matters: whether to trust or feel guilty, to empathize or be embarrassed. People who meditate, according to some studies, have a thicker insula.

As it turns out, the insula's poetic merging of the physical and emotional helps to explain much of our unconscious behavior. People who are socially rejected—given the cold shoulder—get chills and crave warm food such as soup.

Warm springtime conditions are related to a better mood and expanded memory, but both take a plunge in the summer heat. Extreme temperatures make people hostile and aggressive, and violent crimes occur more often in the hotter months. Drivers honk more in heat waves. When you're hot and tired, you're more likely to interpret another person's neutral expression negatively.

our perception of reality still relies on sensory experience. Though we may wish for it to be otherwise, our minds cannot be separated from our bodies. And our bodies depend on the environment—what we encounter here on planet Earth

Scientists think the brain's prefrontal cortex processes experiences, using sensory input from the eyes, ears, nose and mouth, sorts them into categories, and tags the various memory fragments with specific associations (smells of home, friends from camp, bugs, a pet, for example). When a memory cue comes in, the brain searches its circuits for related fragments and assembles them like a jigsaw puzzle. Some fragments bring associated fragments along, which is why one old memory often leads to others. Tastes and smells are particularly evocative

Each time people bring up the same memory, those related fragments and circuits become stronger. "When you are 80 years old, remembering your kindergarten days, it's really the memory of a memory of a memory," says Dr. Devi. That may help explain why children's earliest memories are so unstable: Their neural traces are weak and shallow, whereas the few memories we revisit as we get older lay down stronger traces. Still, because the brain is constantly reassembling the fragments, they are vulnerable to distortion.

And Mr. Peterson simply ignores several decades worth of recent studies in cognitive science by researchers such as David Povinelli, Bruce Hood, Michael Tomasello and Elisabetta Visalberghi, which have elucidated very real differences between human and nonhuman minds in the realm of conceptual reasoning, particularly with respect to what has been termed "theory of mind." This is the uniquely human ability to have thoughts about thoughts and to perceive that other minds exist and that they can hold ideas and beliefs different from one's own. While human and animal minds share a broadly similar ability to learn from experience, formulate intentions and store memories, careful experiments have repeatedly come up empty when attempting to establish the existence of a theory of mind in nonhumans.

This not only detracts from the argument Mr. Peterson seeks to make but reinforces the sense of intellectual parochialism that is the book's chief flaw. Modern evolutionary psychology and cognitive science have done much to illuminate the evolutionary instincts that animate complex human mental processes. Unfortunately, in his determination to level the playing field between human and nonhuman minds, Mr. Peterson has ignored at least half his story.

The two types of well-being aren't necessarily at odds, and there is overlap. Striving to live a meaningful life or to do good work should bring about feelings of happiness, of course. But people who primarily seek extrinsic rewards, such as money or status, often aren't as happy, says Richard Ryan, professor of psychology, psychiatry and education at the University of Rochester.

But such unpredictable times make the stabilizing hand of government more important than ever. We need institutions that take some of the ambiguity out of the marketplace, that allow us to plan as rationally as possible. Instead, we're stuck with a tax code and a regulatory horizon that seem to be doing the opposite.

consultancy called Cultural Logic "that uses insights from the cognitive and social sciences to advise nonprofits on how to effectively communicate issues of public interest." Take global warming. The public is increasingly skeptical of cataclysmic climate claims, and their lack of faith, Mr. Geary says, is the result of faulty metaphors. Cultural Logic found that the average person doesn't understand what the metaphorical phrase "greenhouse gas" means and so is unmoved by it.

"Jeopardy," with its puns and strangely phrased clues, seemed too hard for a computer. IBM already had teams building machines to answer questions, and their performance, in speed and precision, came nowhere close to even a moderately informed human. How could the next machine grow so much smarter?

He was comfortable conversing about everything from the details of computational linguistics to the evolution of life on Earth and the nature of human thought. This made him an ideal ambassador for a "Jeopardy"-playing machine. After all, his project would raises all sorts of issues, and fears, about the role of brainy machines in society. Would they compete for jobs? Could they establish their own agendas, like the infamous computer, HAL, in "2001: A Space Odyssey," and take control? What was the future of knowledge and intelligence, and how would brains and machines divvy up the cognitive work?

It’s possible that admissions officers also have a bias toward round numbers. (The students clearly think they do.) But examining the admissions decisions at one elite college, and one business school, the researchers couldn’t spot one.

These results capture the stunning developmental inequalities that set in almost immediately, so that even the mental ability of 2-year-olds can be profoundly affected by the socio-economic status of their parents. As a result, their genetic potential is held back.

Such statistics have led many researchers to highlight the importance of improving the early-childhood environments of poor children.