There is an experience which is common to every religious belief system. It is the sense of coming face-to-face with something far greater and immeasurably more vast than yourself, glimpsing the essence of reality and being overawed by it. In the Buddhist tradition, it is often referred to as satori; Christian charismatics call it the sense of God's presence or the Holy Spirit moving in one's heart; while a devotee of a mystical sect might refer to it as union with the Absolute. More commonly, it is simply referred to as the human sense of spirituality. Whatever one chooses to call it, though, it is a powerful and profoundly moving experience, one which often has long-lasting effects on a person's view of the world. The reality of this occurrence may well be a major reason accounting for the popularity and power of religion even today.

Some readers undoubtedly will have noticed the word "reality" in the previous sentence. That is not a mistake or a careless phrasing; I fully agree that these experiences are real. I should know, because I occasionally have them myself.

That might, at first, seem like a strange admission for an atheist to make. But the crucial point is that I agree with theists that the feelings associated with these experiences are real; we merely differ on what causes them. I maintain that love, joy, wonder, awe, and all the other feelings humans experience are caused by electrochemical activity within the brain, although I do not believe that this makes them any less real or meaningful. However, the physical basis for these feelings is surveyed in "A Ghost in the Machine", and so will not be further discussed here. The topic of this essay will instead be how atheism can in fact be a far more spiritual experience than any religion.

Imagine the first human communities, the first civilizations to arise in the history of our species. The planet they lived on would have been very different from the one we are used to today. From space, it would have been utterly darkened on the night side, without a single glimmer of light to suggest that it was inhabited. The night sky as these people would have seen it, pure and dark, is a thing almost unimaginable to many people today. In the present era, those who dwell in large cities can see a few dozen stars at night; those who live in suburban areas, probably a few hundred. These people would have seen thousands, each one as sharp and brilliant as diamonds spilled across the firmament. On clear nights, the Milky Way itself must have been visible, the plane of the galaxy like a pale misty arch spanning the sky. To lie back and take it all in must have induced vertigo, as if the cosmos was not overhead but below, a starry abyss into which one could fall and be lost forever.

The awesome majesty of the night sky would have been only the most obvious reminder of something these people must have known very well: they were largely at the mercy of an indifferent and often hostile universe, fearful of forces beyond their control. In light of this fact, and given a basic knowledge of human psychology, what happened next is not difficult to understand. They created, largely unconsciously, a system to give them the feeling of control over the world they craved - a belief system in which nature was ruled over by spirits and deities that could be assuaged, bribed, or propitiated. As this theology evolved over time, it added a new proposition from which people could derive further comfort and feelings of control: the gods care about us, they are on our side, and regardless of appearances, they will ensure that things turn out right for us in the end.

For the most part, this pattern has continued today. Though we have had some degree of success at bringing the forces of nature under our influence, for the average person life is still a great struggle in the shadow of events we rarely understand and can even more rarely control. The universe is too big, too impersonal, too difficult to understand. When people put it on one side of the scale and themselves on the other - because the ego, whether consciously or not, tends to judge all things in relation to itself - it does not balance. They feel small, lost, afraid. To counterbalance the scale, people seize on the grand assertion: "The creator of the universe is interested in me personally!"

The effects of such a belief have reverberated throughout history. The ancient Greeks put heroes and gods in the night sky, as if its only purpose was to act as a larger mirror of our daily lives. Christianity went even farther, and for centuries clerics declared the Earth to be the unmoving center of the universe, the axis of creation around which everything else revolved. Those who spoke out against this notion were threatened with, and sometimes actually suffered, imprisonment, torture and execution, with such fury did the church react to anyone who dared to suggest that human beings were anything less than completely superior. In fact, almost every religion human beings have ever invented has had a core belief that humanity was in some way central to the universe. Yet for all their exaltations of humility, how many of them ever imagined that we were but an infinitesimal part of an enormous cosmos, utterly insignificant to the running of the whole?

This, then, is the spirituality of theism: God made the world for us to live in and watches over us from his heaven; he cares about us and will save us in the end, so long as we worship him and remain appropriately respectful of his power. No matter how bad things may seem, he has a plan, and it is our lot to have faith in him and trust that all will work out for the best.

If this is the spirituality of a theist, what constitutes the spirituality of an atheist? To be sure, some people, and not just theists, would regard that as an oxymoron. But I do not. While spirituality is commonly defined in terms of belief in supernatural beings, I believe there is a better and more fundamental definition: a sense of the sacred, of the things that are highly valuable and worthy of reverence. In sum, I consider spirituality to refer to the sense of awe and wonder, a recognition of the deeper and more profound aspects of life. In this sense, an atheist can be at least as spiritual as any theist.

What, then, speaks to an atheist's sense of the spiritual? There is no universal answer to this question, but in my personal experience, we can find awe and wonder in the most unexpected and, often, the most simple places. As small a thing as it seems, I have always enjoyed, on a winter night, watching snow falling through lamplight. Against the darkened sky the falling snow is almost invisible, but where it passes through the light it seems to glow, making the edge of the light visible in turn. Of course, it is impossible to watch every falling snowflake; there is so much data that the visual system is overwhelmed, and the result is merely white noise, evanescent patterns that are gone as soon as they are created. It is beautiful, almost holy to watch the snow silently fall.

But just because it is possible to find beauty in the small things does not mean that the greater things do not hold a power and a majesty all their own. During clear, dark nights, when I look up at the endless starry infinity and try to hold that entire expanse in my head, and discover anew that this is an impossible task - at such times, I experience a genuine sense of awe. The universe we live in is a far greater and more incredible place than we can imagine, or can imagine.

No matter how familiar the fact is, I still find it astounding to realize that each of those points of light in the night sky is a sun - from ordinary yellow stars like our own to hot blue supergiants and ancient swollen red giants, and every kind in between. But our universe holds more wonders beyond this. There are great nebulae light-years across, misty stellar cradles where newborn stars emerge from disks of gas and dust. Some of those distant twinkles are not just stars but entire galaxies like our own, island universes of hundreds of billions of suns in the shapes of enormous rotating spirals and dense globular clouds and great starry walls. And scattered throughout this cosmos are countless worlds, planets born of the heavy elements forged in the hearts of massive suns and blown back into space in those suns' violent death throes, enriching the interstellar medium with a wealth of new possibilities. At least one of those worlds bears self-aware, intelligent life - at least one, and possibly many more.

And in comparison to all this, what are we? What is the place of humanity in the grand scheme of things?

There is a photo, taken in 1990 by one of the Voyager spacecraft from the edge of interstellar space, over three billion miles from home. As it sailed away out of the solar system, never to return, it pointed its camera backwards and took one last picture of the planet from which it came. In the picture, the Earth is a single lonely twinkle, a pale blue dot against a background of all-enveloping darkness. A golden sunbeam illuminates our planet, as if it were a single dust speck floating by itself in a huge drafty hall.

The longer one looks at this picture, the more profound is the realization: that tiny, far-off glimmer is our home. Our lives, as well as the lives of everyone we know or have ever heard about, took place there. All of history - all the madness and the chaos, all the struggle and the bloodshed, all the petty everyday difficulties and all the vast conflicts, all the crushing losses and marvelous triumphs of the human species - took place on that pale blue dot, affecting nothing beyond it, while all around us the cosmos continues on its vast revolutions, unperturbed.

This knowledge, paradoxically, is both an uplifting and profoundly humbling experience, revealing our utter insignificance and simultaneously elevating our lives beyond measure. In our telescopes, we see light that was emitted long before the Earth ever existed. While it traveled across space, our solar system formed from a disk of dust and gas, our sun ignited and began to shine, our planet coalesced and began to travel in its orbit, and life arose and diversified over billions of years until it became able to know itself. When I contemplate these things, this is when I experience wonder. We are stardust, part of the cosmos that is our home. We are, in a sense, the universe examining itself. From our tiny and remote corner of the cosmos, we have gazed across the light-years, unraveled the natural laws that hold on the very largest of scales, and traced our own origins all the way back to the Big Bang. How can such profound understanding not instill in us a sense of awe?

The truth is far more inspiring and powerful than religious mythology. Knowing that the cosmos was not made just for us opens up whole new vistas of wonder and mystery - it makes it all the more surprising and amazing that we are here regardless. Our own existence, and our consciousness of that existence, is a thing so incredible and strange that it alone qualifies as the greatest miracle in our experience. Our life is a glorious mystery, and only by living with our eyes on the ground can we ignore this fact. When one truly understands this, one stands in awe of everything - and that is the spirituality of an atheist.

The spirituality of theism, by contrast, is very human-centered, arrogantly anthropocentric. It postulates that everything that exists does so only for our benefit, that the universe is ultimately subservient to us. It imagines that this universe of a hundred billion galaxies each made up of a hundred billion stars was created for the sake of one star, and that that one star in turn was created only so that it could warm a planet a millionth of its size, and that that entire planet and its gloriously complex four-and-a-half-billion year history of life was created only for the sake of the beings who currently bestride its surface. While astronomers look out into space and see the titanic deaths of stars and the collisions of entire galaxies, theism claims that the life of a single man or the formation of a tiny fiefdom hundreds or thousands of years ago was the most important thing that ever happened in the history of the cosmos. How could this view not rob life of its beauty and its mystery? Instead of viewing the cosmos as an awesome mystery awaiting us, a distant frontier we have yet to discover, this outlook makes it more like scenery, an arbitrarily contrived puzzle made just to keep us busy. Instead of viewing our conscious existence as an incredible gift, this outlook naturally leads a person to expect it and take it for granted. The truth is that an atheistic worldview is at least as compatible with the human sense of spirituality as any religious worldview is, and by no means denies the vital sense of awe and wonder that gives meaning and worth to human life. All atheism denies is that we need any invented miracles to give importance to the genuine miracles that surround us every moment of our lives.