When I tell people that the work we do is teach people how to live happy lives, I like the bewilderment in their faces. It is so simple and almost so daring.

Such a quest is supposed to be flimsy.

Except that it isn’t. Of course. It’s the whole point of being human.

We have spent millennia running against this profound truth that Aristotle masterfully presented 2,300 years ago in the Nicomachean Ethics: that happiness is the ultimate purpose of human existence.

The reason we run away from this truth is that happiness – or the more wholesome twin, joy – is often elusive. And because it’s so unfamiliar for so many of us, we find it terrifying.

“If you ask me what’s the most terrifying, difficult emotion we feel as humans,” Brené Brown told Oprah in 2013, “I would say joy.”

She explains: “How many of you have ever sat up and thought, ‘Wow, work’s going good, good relationship with my partner, parents seem to be doing okay. Holy crap. Something bad’s going to happen’? You know what that is? [It’s] when we lose our tolerance for vulnerability. Joy becomes foreboding: ‘I’m scared it’s going to be taken away. The other shoe’s going to drop…’ What we do in moments of joyfulness is, we try to beat vulnerability to the punch.”

If we can look that fear full in the face, I can testify with my own life, we can find joy every day, in many, many more moments than we can feel anything else.

Joyful people, Brown said, do not allow fear to take away from fully experiencing joy. It’s like we think, “things are going too well… I’m too happy… something bad is sure to happen!” and so we don’t allow ourselves to feel joy to the fullest.

You’re not doing yourself any favours by shrinking back from joy, and the happiness that is its fruit.

Lean into it. It’s your birthright.

Today, on yet another commemoration of the International Day of Happiness, give yourself the gift of remembering that. And believing it.