What is our purpose?

Like all evolutionary adaptations, happiness first occurred as a genetic variation, but persisted because it helped us stay alive.
Happiness describes a range of emotions, from pleasure to glee to contentment. But in the context of evolution, the happiness that proved most useful was the tingle of delight we feel when we’re met with unexpected good fortune.

That sensation is fueled by dopamine, a chemical in the brain associated with motivation and reward-seeking behavior. Scientists who study dopamine know it increases when we’re pleasantly surprised, but not when we’re merely satisfied.

Survival back then was often binary, where one person’s gain was another’s loss, particularly when it came to finding mates. As a result, we’re primed to take pleasure in the downfall of others, the form of happiness we know as schadenfreude, according to David Buss, a psychology professor at the University of Texas.

Similarly, some manifestations of happiness that benefitted early humans are now detrimental to our emotional health.

"The way that evolution by selection works is that it’s inherently competitive," says Buss. “The two ways to achieve it are to enhance ourselves or to facilitate our enemies’ falling. It’s not a rosy picture of human nature, but it’s who we are.”

While schadenfreude and similar emotions might have helped our ancestors survive, they’re less useful now, when cultural mores urge us to be charitable toward rivals, and frown upon delighting in others’ misery.

For most of us, unhappiness is a more powerful driver than happiness. Because unhappiness motivates us to make changes, we’re hard-wired not to remain too happy for long.

In a series of experiments, psychologists Daniel Kahneman and Amos Tversky demonstrated that we feel the sting of loss more than we enjoy the gain of the same amount. “Pain is more urgent than pleasure,” they wrote in an influential1991 paper that helped Kahneman win a Nobel prize.

That’s probably because unhappiness was ultimately more useful for survival. Unhappiness, and its cousins misery and pain, could prevent starvation and dismemberment, while happiness was a more subtle goad toward the better things in life.

Not all forms of happiness can be explained by evolution, particularly more recent manifestations. Culture plays an important role in adaptation, as different groups adopt different behaviors that help them navigate their unique worlds, Barkow said.

Likewise, understandings of happiness have changed over time. How different societies viewed happiness helped shape their culture and survival strategies.

In ancient China and Greece, happiness was associated with luck and good fortune, a result of external factors that couldn’t be controlled. Over time, as humans gained more mastery over their living conditions, happiness came to be perceived as something an individual could control.

In a 2015 study, researchers led by Shigehiro Oishi of the University of Virginia looked at how happiness was used in every State of the Union address made by US presidents to that point. Early presidents talked about “happiness” as good fortune and prosperity, while more recent uses took on the sense of personal well-being and life satisfaction. The authors theorize that as the US and its citizens grew more prosperous, "people’s perception of personal control in life also increased, and made the fortune-based definition of happiness look obsolete."

In countries where happiness is understood as the result of individual actions, such as the US, people are more likely to make decisions to pursue it. In countries like Japan or Russia, where happiness is understood to be reliant upon fortune, decisions are more likely to be made for reasons other than to maximize happiness.

Never before have expectations been so high about what human beings can achieve with their lifespan. We're told, from many sources, that anyone can achieve anything. We've done away with the caste system, we are now in a system where anyone can rise to any position they please. And it's a beautiful idea. Along with that is a kind of spirit of equality; we're all basically equal. There are no strictly defined hierarchies. There is one really big problem with this, and that problem is envy. Envy, it's a real taboo to mention envy, but if there's one dominant emotion in modern society, that is envy. And it's linked to the spirit of equality.

And yet, they're not. So there's a spirit of equality combined with deep inequality, which can make for a very stressful situation.

There's a real correlation between a society that tells people that they can do anything, and the existence of low self-esteem. So that's another way in which something quite positive can have a nasty kickback. There is another reason why we might be feeling more anxious --about our careers, about our status in the world today, than ever before. And it's, again, linked to something nice.

You know, in the Middle Ages, in England, when you met a very poor person, that person would be described as an "unfortunate" -- literally, somebody who had not been blessed by fortune, an unfortunate. Nowadays, particularly in the United States, if you meet someone at the bottom of society, they may unkindly be described as a "loser." There's a real difference between an unfortunate and a loser, and that shows 400 years of evolution in society and our belief in who is responsible for our lives. It's no longer the gods, it's us. We're in the driving seat.

The other thing about modern society and why it causes this anxiety, is that we have nothing at its center that is non-human. We are the first society to be living in a world where we don't worship anything other than ourselves. We think very highly of ourselves, and so we should; we’ve put people on the Moon, done all sorts of extraordinary things. And so we tend to worship ourselves. Our heroes are human heroes. That's a very new situation. Most other societies have had, right at their center, the worship of something transcendent: a god, a spirit, a natural force, the universe, whatever it is -- something else that is being worshiped. We’ve slightly lost the habit of doing that, which is, I think, why we're particularly drawn to nature. Not for the sake of our health, though it's often presented that way, but because it's an escape from the human anthill. It's an escape from our own competition, and our own dramas. And that's why we enjoy looking at glaciers and oceans, and contemplating the Earth from outside its perimeters, etc. We like to feel in contact with something that is non-human, and that is so deeply important to us.