“An apple a day keeps the doctor away.” We all know that healthy habits can help us build a strong body, but how can we live a happy life? Over the past two decades, scientists have identified many techniques to raise our happiness, but these methods cannot work magic. “Things like poverty or injury are obviously going to affect your well-being,” says Laurie Santos, at Yale University. “But for many of us, our happiness is much more under our control than we think.” Her free course, The Science of Well-being, explores evidence-based ways to increase happiness.

For a taste of what the course involves, consider our tendency to compare ourselves negatively with the people around us. By recognizing when those thoughts have started to arise, you can consciously shift the reference point to something more neutral(中立的).With this kind of thinking, you may start to feel more content.

The use of gratitude journals, where you regularly count your blessing, work on a similar basis. We have a tendency for “hedonic adaptation”, essentially getting used to the good things in our life over time, and taking them for granted, so they no longer bring us the same interest—we should delay that process.

Other tips like small acts of kindness may surprise you with rewarding experience. However, those approaches to happier life should be used carefully. There is now some evidence that pursuit of happiness can have the opposite effect if it becomes time-consuming. Keeping a gratitude journal appears to be effective if it is used once a week. It seems that the technique may become a burden if it is practiced too regularly.

There seems little doubt that we can learn to be happier, but we should recognize that the path to a better life is with ups and downs. You cannot remove every negative feeling, but with some science-backed strategies, you can shift the balance so as to experience more positive feeling than negative ones.

Unlike so-called basic emotions such as sadness, fear and anger, guilt emerges a little later, in line with a child's growing grasp of social and moral standards. Children aren't born knowing how to say “I'm sorry”; rather, they learn over time that such statements appease parents and friends—and their own consciences. This is why researchers generally regard so-called moral guilt, in the right amount, to be a good thing.

In the popular imagination, of course, guilt still gets a bad reputation. It is deeply uncomfortable—it's the emotional equivalent of wearing a jacket stuffed with stones. Yet this understanding is outdated. “There has been a kind of revival or a rethinking about what role guilt can serve”, says Amrisha Vaish, a psychology researcher at the University of Virginia, adding that this revival is part of a larger recognition that emotions aren't binary-feelings that may be advantageous in one context may be harmful in another. Jealousy and anger, for example, may have evolved to alert us to important inequalities. Too much happiness can be destructive.

And guilt, by prompting us to think more deeply about our own goodness, can encourage humans to make up for errors and fix relationships. Guilt, in other words, can help hold a cooperative species together. It is a kind of social glue.

Viewed in this light, guilt is an opportunity. Work by Tina Malti, a psychology professor at the University of Toronto, suggests that guilt may compensate for an emotional deficiency. In a number of studies, Malti and others have shown that guilt and sympathy may represent different pathways to cooperation and sharing. Some kids who are low in sympathy may make up for that shortfall by experiencing more guilt, which can control their disgusting behaviors. And vice versa: high sympathy can substitute for low guilt.

In a 2014 study, for example, Malti looked at 244 children. Using caregiver assessments and the children's self-observations, she rated each child's overall sympathy level and his or her tendency to feel negative emotions after moral wrongdoings. Then the kids were handed chocolate coins, and given a chance to share them with an anonymous child. For the low-sympathy kids, how much they shared appeared to turn on how likely they were to feel guilty. The ones more likely to feel guilty tended to share more, even though they hadn't magically become more sympathetic to the other children.

“That's good news,” Malti says. “We can be prosocial because we caused harm and we feel regret.”

We like to think we can read people like a book, relying mostly on facial expressions that give away the emotions inside. But when it comes to the strongest emotions, we read much less from facial expressions than we think we do. In fact, even though we believe it’s the face that tells the story, we’re typically reading something very different: body language.

That’s the new finding from a study published this week in the journal Science. Researchers from Princeton, New York University, and the Hebrew University of Jerusalem presented volunteer study participants with a series of pictures showing people experiencing extreme emotion, either positive or negative. The images included professional tennis players who had just won or lost a point in a major match.

In some of the images, researchers only show the study participants a face; in others, only a body; and in others still, both the body and the face. You might think it’d be obvious from a face whether he has just won Wimbledon. But it turns out it isn’t.

“The striking finding was that our participants had no clue if the motion was positive or negative, when they were judging faces only,” says lead study author Hillel Aviezer from Hebrew University. “By comparison, when they were judging the body (with no face), or the body with the face, they easily told positive from negative expressions.”

The findings are doubly surprising because the study participants themselves were convinced that they recognized the emotions from the faces, not from body language. “They even had their own theories about what part of the face was most important — but this was a false idea,” Aviezer says. He adds that we do, of course, read a great deal of emotional information from faces but only in certain situations.

“I think the findings may have some clinical applications,” he says. “Consider populations such as individuals with autism (孤独症). We know these people often have difficulties with recognizing facial expressions,” he says. “Until now we have been trying to help them by training them to better understand just the faces. But our work suggests that perhaps we should teach them how to recognize emotions from the full person.”