One aim is to reveal how our relationship to work —in the broadest sense—is more fundamental than that imagined by the likes of Keynes. The relationship between energy, life, and work is part of a common bond we have with all other living organisms, and at the same time our purposefulness, our infinite skillfulness, and ability to find satisfaction in even the mundane are part of an evolutionary legacy honed since the very first stirrings of life on earth.

Think back for a moment on that someone you know who lived a full life. You get the sense, don’t you, that they were on to something. That they had somehow cut through all the noise, and tuned themselves into a signal only they could hear. And they didn’t do this in spite of their work. Rather, they seemed to be doing it through their work. Their loves and their work were inextricably linked.

In their telling, “work” does not simply mean “job.” It is not merely manual or knowledge labor. Instead, “work” is anything of value they created for someone else.

Your life should be an ongoing search for love. Sometimes high performance will flow from your love, and sometimes it won’t. But in all cases, more love in your life means a fuller life.

Instead, a healthy life is one where you are in motion, where you are moving through life—all aspects of your life—in such a way that you draw strength and love from it, and this then gives you the energy you need to keep moving.

This means to live happily and fully, you have to express your loves. Yes, they spring from within you, but then they demand expression. You’ve got to get them out somewhere, somehow, turn them from loves into actions, from passions into contributions. And when you do, your life feels coherent and authentic, and you know, you just know, in every fiber of your being, that you are on your path.

That said, there are three prevalent sources of fuel for the inner fire across the vastly different lives in the study. In addition to love of the doing, the two others are:

Extend Out/Circle Back: This is a continuous dynamic process of extending yourself— growing, learning, experimenting, expanding capabilities, discovering new encodings— while simultaneously drawing upon encodings discovered and capabilities developed earlier in life.