It is impossible for the finite human mind to fully comprehend the nature of infinity. We all understand the idea on a surface level, but when we try to push deeper, things invariably fall apart. When we try to imagine, for example, an infinite number of soccer balls or an infinitely long stretch of rope, we end up with a "very large" amount that comes nowhere close to doing justice to the concept. There is always a nagging sense that the "end" is just around the corner—that if we just keep at it long enough, we will be able to rise above it all and take in its sweeping splendor all in one glance. This is, of course, a fantasy.
It's important to understand that infinity is not strictly a number. It is a concept that represents a quantity that is so great as to be boundless and without end. What's more, infinity regularly violates our common sense. If you owned a hotel with infinite rooms, all occupied, you could still make space for infinite new guests simply by moving each old guest from Room #1 to Room #2, Room #2 to Room #4, Room #3 to Room #6, and so on. The set of all fractions is just as large as the set of all whole numbers—although the set of all decimal numbers is even larger. This is the sort of counter-intuitive madness we must deal with when we try to grasp at this concept.
Eternity can be defined simply as an infinite length of time. In this essay I will present a thought experiment designed to help catch a glimpse of eternity's sheer, ludicrous magnitude, to understand it to the greatest extent possible—which, unfortunately, is still not much at all. In the future I will refer back to this experiment to discuss its theological implications. To get the full experience, please take your time and visualize the imagery as vividly as possible.
Imagine that you have decided to spend the day at the beach. Get out of your car and walk along a short concrete path surrounded on either side by grassy lawn. Descend a few steps and look around. The ocean is in front of you, the sky above is a deep and cloudless blue, and an expanse of fine white sand stretches to your left and right for as far as you can see. Sit down and take a pinch of sand with your thumb and index finger. From this pinch, isolate a single grain, which is no larger than the period on this page, and place it in the palm of your hand.
Concentrate on this grain of sand, and imagine that it represents your full lifetime, from birth up until this very moment. In order to fully comprehend this idea, go through your entire life, starting with your earliest memory and slowly working your way through the years. To the best of your ability, recall your various triumphs and failures, but try to remember the more tedious in-between moments as well. Remember every boring lecture in school, every night spent tossing and turning with insomnia, every lengthy sermon in church, every dull wait at the doctor's office, every long delay spent stuck in traffic. Realize that for each moment you can recall, there are hundreds if not thousands more that you cannot. Once the full weight of these memories is clear to you, focus on compressing these memories into the grain of sand. Whether it represents 10 years, 50, or 100, this grain of sand is your life.
Now with your other hand pick up another pinch of sand and slowly sprinkle it into the palm holding the single grain. Each new grain of sand is another lifetime's worth of lunches eaten, books read, movies watched, showers taken, papers written, and so on. Feel the innumerable slight taps as every individual grain makes contact with your hand. What you now hold in your hand is equivalent to several thousand years. Now with your free hand take a great handful of sand and let it slowly out into the other palm. As you do, try to visually isolate the single grains that still represent your full lifetime, birth to present. They probably fly by too fast to identify, but that does not make them any less real than the grain you started out with.
By now you should have a considerable pile of sand in your open palm, representing at least several million years. Dump the pile back onto the beach. Find a single grain to serve a reference, then slowly look up and down the beach to the horizon to the left and right. Try to understand fully that the entire beach consists of countless billions of grains—countless billions of lifetimes—exactly like the single reference grain. Imagine what it would mean to live out these lifetimes one by one. After experiencing year after year, you would finally be entitled to discard a single grain… and pick up the next. Goodness, you think. Infinity really is quite something. But we have only just begun.
Facing forward, you find that the ocean has vanished, replaced only with more sand—it was, apparently, just a mirage. Behind you there are no longer any steps, no grassy lawn or parking lot: only more sand. While before you saw a very long but nevertheless thin strip of sand, it now surrounds you in a flat expanse extending in all directions—hundreds of quadrillions of years of life that you are destined to live out.
Now stand up and go for a brisk jog. After a few miles you stop, panting, sweat rolling down your face. You kneel on the ground and begin to dig with your bare hands, scooping out millions of years at a time, until you have a hole several feet deep. At last, you have found it: a grain of sand representing your full lifetime. The point is that this grain, like countless others, was entirely hidden from you. It was the furthest thing from your mind, yet it still represents the same long drives and meals and lectures and workdays as the others. While it may be nothing special, it still represents many quite real and concrete years that you must live through on your endless journey through eternity.
Look up at the sky and notice that it has become filled with some unusually dark clouds. As you try to understand what makes them so peculiar, you feel a sting on your face—the sting of a thousand arguments between you and your loved ones. It begins to drizzle, then rain, then pour sand all across the desert landscape; each grain that hits your skin carries its own individual bite. The downpour becomes a deluge of such proportions that you must continually move your feet so as not to sink into it. As great heaps of sand pound against your head, you desperately fight the flood of lifetimes, but they soon overwhelm you. In seconds, you are buried up to your knees, to your waist, to your neck, and finally you are buried alive, crushed as quintillions of years press in against you from all sides.
|One galaxy. Of 80 billion.|
Now take that image of the observable universe filled to the brim with tiny grains of sand, each representing your entire life's worth of experiences and each no bigger than a period on this page, and zoom out. Zoom out further and further, until the entire mass looks tiny—no larger than a grain of sand. Imagine yourself back on the beach holding that single grain of sand. The grain now represents a universe that is itself filled with grains of sand. Look to your left and right, taking in all the billions of other grains, all of which represent other universes filled with countless grains that all represent lifetimes.
Imagine going through the entire cycle in fast forward several times: a grain of sand, a pinch, a pile, a beach, a desert, a deluge, a solar system, a galaxy, a galaxy cluster, a universe that becomes a grain. Each full cycle multiplies the amount of time you must live through to such an extent that it is beyond my ability to describe it. Go through the cycle thousand times, a million, a billion. For what ridiculous, incomprehensible length of time must you now toil through your dreary existence?
The answer should make you want to vomit: it doesn't matter. Having gone through this cycle one time or a billion makes no difference. You are still no closer to the end of eternity than when you began. This is not meant in any figurative sense. After all of those mind-melting eons, you literally may as well not have started at all. You are zero percent of the way through your journey. But though your brain has long since turned to mush from the sheer accumulation of experiences, there is no giving up. You must press on and on through a life that is, in the truest sense possible, without end. That is the meaning of eternity.
Please do not get the impression that having gone through this exercise you are really any closer to understanding eternity. You have merely imagined a "very long" interval of time and acknowledged that this interval is nothing in comparison to the genuine article. In understanding this, you are simply waving the white flag that should have been waving all along. At best, you now comprehend that you can never comprehend eternity.
As I suggested earlier, both the nature of eternity and our ability to comprehend it have important religious implications. I will refer back to this thought experiment in later posts when discussing subjects such as the doctrine of hell.