Yet psychologists now know that only a small percentage of people develop the full-blown disorder while, on average, anywhere from one half to two-thirds of trauma survivors exhibit what’s known as post-traumatic growth. After a crisis, most people acquire a newfound sense of purpose, develop deeper relationships, have a greater appreciation of life and report other benefits.

It’s not the adversity itself that leads to growth. It’s how people respond to it. According to the psychologists Richard Tedeschi and Lawrence Calhoun of the University of North Carolina at Charlotte, who coined the term “post-traumatic growth” in the 1990s, the people who grow after a crisis spend a lot of time trying to make sense of what happened and understanding how it changed them. In other words, they search for and find positive meaning.

In modern psychology research, this is known, a bit unfortunately, as “benefit finding.” Mr. Frankl called it “the human capacity to creatively turn life’s negative aspects into something positive or constructive.” Of course, some people are naturally more hopeful than others. But the success of psychological interventions like meaning-centered psychotherapy — developed by Dr. William Breitbart at Memorial Sloan Kettering Cancer Center and his colleagues to help terminal patients cope with death — reveals that even the most despairing individuals have the capacity to find meaning in a crisis.

It may seem inappropriate to call on people to seek the good in a crisis of this magnitude, but in study after study of tragedy and disaster, that’s what resilient people do. In a study of over a 1,000 people, 58 percent of respondents reported finding positive meaning in the wake of the Sept. 11 attacks, such as a greater appreciation of life and a deeper sense of spirituality. Other research shows that benefit finders grow not only psychologically but also physically. Heart attack survivors, for example, who found meaning in the weeks after their crisis were, eight years later, more likely to be alive and in better health than those who didn’t.

This doesn’t mean that people should endure adversities with a smiling face. In fact, Mr. Frankl specifically said that tragic optimism is not the same thing as happiness. “To the European,” he wrote, “it is a characteristic of the American culture that, again and again, one is commanded and ordered to ‘be happy.’ But happiness cannot be pursued; it must ensue. One must have a reason to ‘be happy.’”

He was right: In American culture, when people are feeling depressed or anxious, they are often advised to do what makes them happy. Much of the pandemic-related mental-health advice channels that message, encouraging people to distract themselves from bad news and difficult feelings, to limit their time on social media and to exercise.

I’m not suggesting those aren’t worthy activities. But if the goal is coping, they do not penetrate into the psyche as deeply as meaning does. When people do things that make them happy, like playing games or sleeping in, they feel better — but those feelings fade fast, according to research by Veronika Huta of the University of Ottawa and Richard Ryan of the University of Rochester.