Martin Seligman, the father of "positive psychology," found that about 60% of happiness is determined by genetic factors (what we inherited from our family and the unique temperament with which we came into the world) as well as by our environment. The rest is in our hands.

Although seeking pleasure may be thought to be a goal of happiness, what really seems to be most important is leading a life of engagement and meaning.

Desiring to be happy doesn’t mean you will be happy all of the time, but there are many things you can do and practice to increase your chances, or at the very least learn to look on the brighter side of life.

Here are 9 personality traits truly happy people have that set them apart from others.

1. Happy people like themselves.

Happy people are satisfied and appreciative of who they are as individuals. There’s always room for improvement, but generally, they know and truly, genuinely like who they are.

They are confident, optimistic, resilient, and adaptable. They can see humor even in things that don’t seem funny on the surface. They know they are good people, through and through.

Photo: George Milton / Pexels

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2. They are self-reliant.

They look within themselves to find answers and solutions. They don’t see themselves as victims; rather, they view themselves in quite a positive light.

Many notable people have written about the true self vs. the false self, the idealized self vs. the realized self, and so on. In other words, happy people have learned what is most important to them, what is true for them, and what things are non-negotiable, as opposed to allowing others to dictate and impose beliefs upon them.

3. They don't let their relationships define them.

Their relationships are not about “you complete me." Instead, happy people are complete within themselves, having done the required inner work to know who they are.

They view relationships as an extension to, not the basis of, the human experience. It is not about “what can you do for me,” it's about the sense that essential relationships are unconditional.

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4. Happy people live in the moment.

For happy people, living in the moment means appreciating every single second they breathe. They embrace change and trust that everything happens for a reason. Rather than wishing for moments of the past or future, they are here, right now, in the present.

5. They practice gratitude for even the small things.

They appreciate the simple pleasures of life — the smell of rain, a delicious meal, or even the first sip of coffee in the morning. They appreciate everything that happens to them; it’s all an experience, an adventure, an opportunity.

6. They make an effort to be happy.

Because like attracts like, happy people tend to hang out with positive individuals. All things being equal, they tend to look on the brighter side of life, finding a sliver of hope in every poor situation.

They attempt to find solutions and answers that are as close to satisfactory, even if it's not the ultimate desired solution.

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7. Happy people take care of themselves.

They exercise to relieve stress, anxiety, and depression. They eat well and put their mental health above all else. They know how to unplug, distancing themselves from the stresses of life.

Many happy people have a spiritual practice, whether it’s taking a walk in nature or meditating.

8. They consider interpersonal connections of vital importance.

Happy people listen to others and are genuinely interested in what they think, feel, and do — and they engage people in what is important to them. They don’t compare themselves to others and don’t hold a grudge.

They are kind to everyone and often give back to others in whatever way they can.

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9. Happy people control their own life and destiny.

They pursue their ambitions, and don’t let a bad situation defeat them; when something bad happens, they choose to see it as a challenge and then try harder to overcome it.

They don’t sweat the small stuff. They accept what happens in life, especially what can’t be changed — and then they move on.

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Abigail Brenner, M.D., is a board certified psychiatrist in practice for more than 30 years, and author of three books, including "Transitions: How Women Embrace Change and Celebrate Life" and "Shift: How to Deal When Life Changes."

This article was originally published at Psychology Today. Reprinted with permission from the author.