Some people see happiness as the feeling in a small moment - a chat between old friends, a warm meal. Some see it as deeply profound, a kind of enlightenment.
Some of the biggest findings about the science of happiness contradict many people's understandings of how to find joy.
Here are just a handful of those misconceptions.
1. More money does increase happiness - but only to a point.
A higher salary is always nice, but it won't necessarily increase your happiness, a wide body of research suggests. Some early behavioural economics studies found that a salary of roughly US$75,000 a year was the point at which happiness began to plateau.
Follow-up research has found similar plateaus based on the cost-of-living in your particular area. Someone in Atlanta, for example, will hit peak happiness by making roughly US$42,000 a year, while a New Yorker will need to pull in US$105,000.
2. Happiness comes from giving gifts, not receiving them.
Unwrapping presents on a holiday or birthday is undeniably fun, but science suggests the person who bought and wrapped those gifts is gaining more happiness than you are.
A 2008 study found that people's reported levels of happiness jumped when they spent money on others instead of on themselves. A follow-up study in 2013 showed that the finding applied to people in 136 countries, not just those in North America.
And earlier this year, a study showed a neural link between generosity and happiness, further cementing humans as fundamentally social animals.
3. Having too much freedom of choice can reduce happiness.
It's better to have some choice instead of no choice, psychologist Barry Schwartz has said. But it doesn't hold that more choice is always better.
If humans are presented with too many options, their decision-making abilities kind of shut down, Schwartz's research has found. Some neuroscience research has also shown that making choices is exhausting and can hurt cognitive abilities in other areas.
These findings have led Northwestern University neuroscientist Moran Cerf to adopt a surprising habit: He always picks the second menu item on a list of specials to free up his brain for more important choices in the day.
4. Longer vacations aren't always worth it.
The psychologist Daniel Kahneman has written that human beings are actually composed of two distinct selves: the experiencing self and the remembering self. The experiencing self lives in the moment, while the remembering self savours life in hindsight.
Vacations are the ultimate ticket to happiness for many people, but Kahneman suggests that from the point of view of the remembering self, two-week vacations aren't twice as good as one-week trips.
Unless you spend each day differently, the memories will all mix together and you won't be any happier for it.
5. No one should try to be happy all the time.
A big misconception about happiness is that it's something to attain, and keep, forever. Science encourages people to reject that mindset and instead view happiness as multi-faceted.
It's possible to have multiple kinds of happiness that contradict each other, such as when you need to turn down dinner invitations because you've committed yourself to working on a new book, or some other long-term goal.
In order to maximise happiness, humans seem to need to know what the bad moments look like - suffering is something to practice, scientists have found.
6. Grudges really do prevent people from being happy.
Confronting negative emotions is difficult, and something a lot of people want to avoid. But a wealth of research has discovered that forgiving others (and oneself) for past misdeeds can go a long way to reducing long-term stress and improving psychological well-being.
A 2015 study also found that letting go of a grudge can lead to improved physical ability. Participants who reflected on a time they forgave someone then jumped into the air reached greater heights than the people who reflected on a time they kept a grudge before jumping.
This article was originally published by Business Insider.