There is a game I played on my iPhone. It’s called One Single Life and I didn’t play it again. The game’s concept is very simple: you run, you jump, and you land on the next building. There is just one catch: if you die, you die. You do not get a second chance. This is one of the most thrilling games I have ever played; the knowledge that my quarter-inch avatar is about to leap quite possibly to his tiny death sends tremors to my fingers. My heart beats fast, and my palms are as dry as dust. I am terrified.

I know this sensation well, and it is the pause before the leap. In my youth, I spent a great deal of my time rock climbing, mostly at indoor rock gyms since the weather was usually bad. Some of the long routes were scary; one curved wholly over the ceiling of the gym, some sixty or seventy feet off the ground. Still, there was always a sense of safety, of a second life: the floor was cushioned, you were roped in, your climbing buddy had you.

But there was a time when a friend and I went walking in the Swiss Alps. I say walking, but we were young and foolish, and couldn’t resist the temptation to race each other up small cliffs here or there, quite proud of our budding climbing skills. This naturally delayed us, and we found ourselves quite late in the day still on a glacier, not even close to where we needed to be, and so decided quite wisely to take a shortcut over a low peak to the north. The peak had looked innocent enough on the map, but when we arrived at its base, we realized we were faced with a hundred-foot cliff face that was not quite vertical…and of course we just had to climb it. After all, it would surely be faster than going around.

I won’t speak of the abandoned Swiss military base at the top of this mountain – that is for another time – but it was halfway up this ridiculously foolish ascent that I first truly realized that I could die. Despite my confidence, the rock was loose, and in grasping for a handhold, the stone simply came free in my hand. For a single, endless moment, I wheeled slowly, sickeningly away from the cliff, releasing the rock and knowing it might hit my friend below me, and all the while grasping in utter desperation at the cliff with the two remaining fingers that attached me to it. Somehow – I have no memory of it to this day – I did not release my grip from the wall. I believe I was in tears when we finally arrived at the top.

The free fall in the stomach, the dryness of hands, the hypersensitivity to every touch and sound, are the hallmarks of standing on the edge of death. Sadly, my experience in the Alps was not the only time this sensation came over me. Countless times since then, I have found myself on that edge, often with a blade to my wrist. I have lived with people who have stood on that edge with me, and we would stare into the darkness together. The sensation, as the steel bites into your skin, or the rope rubs roughly on your neck, is not of pain, or of comfort, or even of anguish: it is the dusty, gliding feeling of standing right on that edge, toes over the abyss, and deciding to leap.

In the end, I never leapt. Some I know did, but were caught, and survived. Some leapt and we never saw them again. I could never overcome the sensation, the thrill of death that had saved me that day in the Alps, and fell back from the edge each time. I was crushed, dismayed, guilty and furious, and all this would collapse into the deadness that I was doomed to live for yet another day; but I was nonetheless alive.

This was all some time ago, and though I still see the edge each day, I keep my distance. I wouldn’t want to fall off by mistake. I can’t convincingly say that the fear of the leap has taught me anything, but I am glad of it, for had I jumped I would not know my wife, and I would not know our son, and the world would have been a darker place.

Still, I wonder at the thoughts of those others, at the moment they chose to make the leap. I imagine it was release – the final decision they would ever need to make was done, and there was no need to look back.