For many assistant professors, the "tenure decision" is one of the most stressful of their lives. For years, they work to obtain a permanent position at a college or university to which they have become attached. If they don't get tenure, they will have to leave.
A question: When assistant professors are denied tenure, what happens to their happiness? As we will see, the answer has important implications for how we think about both individual lives and public policy.
Assistant professors predict that their happiness would be greatly reduced by a negative tenure decision, but they're wrong. After a few years have passed, there is no discernible difference between the happiness of those who get tenure and the happiness of those who do not.
The example shows that people often make inaccurate predictions about how unwelcome events will affect their well-being. Before an election, voters think they will be miserable if their preferred candidate loses, but after just a month, political outcomes don't have much of an effect.
Contemplating a divorce is horrible, but after a period of adjustment, divorced people tend to end up about as happy as they were before. After a while, young people who have lost a limb as a result of cancer show no less happiness than young people who haven't had cancer.
Kidney dialysis patients don't show significantly reduced levels of happiness. After two years, moderately disabled people have been found to return to their pre-disability happiness level. It is remarkable but true that paraplegics are only modestly less happy than other people.
What explains people's mistaken predictions about the effects of bad events and conditions? Two factors are important: attention and adaptation.
When people lose the use of an arm, they don't think, most of the time, about the fact that one of their arms doesn't work. Instead they focus on the central features of their hours and days - their jobs, their meals, their relationships, the book they are reading or the television show they are watching.
When significant losses don't make people miserable, it is because people don't pay a lot of attention to those losses. Nobel laureate Daniel Kahneman describes the phenomenon in a wonderful maxim: "Nothing in life matters quite as much as you think it does while you are thinking about it."
The second factor involves our remarkable power to adapt, which means that our emotional responses to bad events or conditions typically abate as time passes. Those who have been denied tenure, or lost the use of a limb, will react intensely at first, but after a period, the intensity greatly diminishes.
Attention and adaptation also help explain the modest effect of many good events, not just bad ones. After a year, lottery winners aren't a lot happier than they were before.
Marriage is often thought to be associated with increases in happiness, but after a few years, married people tend to be about as happy (or unhappy) as they were before. Apparently, getting married produces a significant emotional "boost," but the boost is usually short-lived.
Some observers have invoked these findings to suggest that human beings have an emotional "set point," and that life events, and even social policies, can have only short-term effects. That's a big mistake.
Some bad circumstances or events have enduring effects. Consider loud, unpleasant noises, which people dislike a lot, and which they don't dislike much less as time passes.
Exposed to nearby highway noise, people show approximately the same level of irritation over a period of more than a year. A study of college students finds greater levels of annoyance at dormitory noise at the end of the year than at the beginning.
Unpleasant noise tends to capture people's attention, and it isn't easy to adapt to it. The example helps to explain two of the most serious sources of long-term distress: chronic pain and mental illness. If you have excruciating headaches or if your back hurts a lot, your life is going to be much worse, because you will have trouble thinking about anything else.
Anxiety and depression take over the mind, and those who suffer from those conditions have real difficulty in adapting (as shown in Scott Stossel's extraordinary new book, "My Age of Anxiety").
Unemployment is also a serious cause of unhappiness. Of course it is hardly an illness, but in terms of people's actual experience, it operates a lot like one, in part because it can take a real toll on people's self-respect.
For public policy, the lesson is straightforward. Human beings recover quickly, and they have an extraordinary ability to adapt to adversity. In allocating our limited resources, we should be devoting much more attention to those problems and conditions for which that ability isn't nearly enough.
Cass R. Sunstein is a professor at Harvard Law School and a Bloomberg View columnist.