Such is the grand ethos that has led one of the world’s eminent schools of public health to turn its attention to, of all things, happiness. The center will focus on how to cultivate lives that are not simply free of disease, but are imbued with purpose, meaning, and optimism. Do that, the logic holds, and physical health should follow. As Kubzansky put it, treating disease has proven an insufficient approach. “There’s increasing recognition that looking at only one side of the health picture may be limiting our ability to help people attain and maintain health.”

“People are increasingly discovering that health is tied to a variety of social conditions—unemployment, recession, the great revolution in communication,” added Kasisomayajula Viswanath, a professor of health communication at Harvard and co-director of the happiness center. The question is, how much can a person do to cultivate positive psychological states on one’s own, and how much is beyond control?

“There’s a lot of folk wisdom around this stuff,” acknowledged Kubzansky. “So people will often dismiss it. Oh, don’t worry, be happy. Everyone’s just got to be happy. Which is fine, until you’re trying to make the case that these are factors we should systematically address either with policy, education, or community investment. Then it’s important to have an evidence base to suggest valid causal factors.”

In recent years, psychologists have repeatedly found that people who have elevated senses of purpose in life do tend to live longer and experience less physical infirmity. Optimism and vitality also seem to be protective of physical health, adds Kubzansky.

These traits resonate with a trend called primordial prevention. As opposed to primary prevention (trying to intervene in a high-risk population before people actually develop a disease) or secondary prevention (trying to prevent complications and progression of disease among people who are already sick), primordial prevention looks at the risks of risks. That is, trying to prevent people from developing the risk factors in the first place. To do that, we need to know what allows people to attain and maintain health over the long term. This is where a person’s state of mind seems to factor most heavily.

“We are seeing risk factors come into play much earlier in the life course than we traditionally thought—surprisingly early,” said Kubzansky. ( Life course being the epidemiological term for life). Indeed, people who are today diagnosed in their 50s and 60s with high blood pressure are likely seeing the result of processes that began much earlier. “There’s already evidence that cardiovascular health is declining by the time people are in their late twenties, which is depressing,” she added. “Once those factors are set, they can be very hard to mitigate.”