You can’t understand someone until you’ve walked a mile in their shoes.

No one liked my FPS mod that gives you three-second snippets from the bios of people you shoot.

To-day we’re going to go down a (violent) rabbit-hole. Are you ready?

Okay. Consider the following narrative concept.

When you kill somebody, you are forced to relive their entire life.

By way of example: suppose to-day you stab your adulterous husband Stan in a fit of passionate rage, and he bleeds to death on the bedroom floor. The moment he gives up the ghost, your life is paused, put on hold, the world shifts, and you wake up in 1984 as Stan the crying infant, newly severed from his mother’s womb and cradled in a nurse practitioner’s arms in Cambria Falls General Hospital. For the next thirty-eight subjective years, you grow up as Stan, shuffling between schools, working cash registers, backpacking in the Rockies, falling in and out and in and out of love, until one winter evening in 2023 your wife Christy learns of your affairs and stabs you to death. At the moment of your death as Stan, the loop is complete, the world shifts back, and you resume your life as Christy again, disposing of the scarlet knife and sobbing into a pillow as the body on the floor pales and the blood encrusts the shag rug. Let’s say you retain all of Stan’s memories as you go forward; they are now also your memories.

Got it?

The motivation behind this premise is empathy. It’s a cruel, monstrous thing to take someone else’s life. If you knew their story, knew it viscerally by living out their whole life, seeing the world from their shoes, understanding all the unique things they brought to the world, how would you feel about having killed them? The sheer weight of what you’ve taken away from the world? In a world where this premise were true, would there still be killing? Would there still be war?

Leaving behind all the hokey idealism, there’d probably still be killing and war and all that. Also things would be a lot weirder, and also scarier.

Let’s suppose that the loop is recursive. If Stan had been deployed in Afghanistan and had killed several mujahideen in a shootout, he would have relived each of their lives, one by one, in chronological order of their deaths. Growing up in the streets of Kabul, Kandahar, Jalalabad, welcoming or resisting the Taliban takeover. It could take a hundred subjective years for Stan to resume living past those thirty terrifying seconds of skirmish. And that’s only if the mujahideen had no killing histories of their own—if they did, as combatants often do, the whole tree of murders could easily take thousands of years to get through. And you, as Christy, would get to relive all of that too as part of Stan’s loop! Get ready for a lot of lives in the armed forces!

But also this premise opens up a lot of scary incentives for killing.

You could kill people to obtain information. By killing Stan, you could learn the identity of his mistress, Jen the waitress—a secret he may have wanted to take to the grave. In the world of this premise, secrets are much more difficult to hold. You’d have to ensure you die a natural death, or at least by no one else’s hand, in order to prevent anybody else from living your life and learning all of your secrets. Morally grey private detectives could kill key figures in a case to learn their stories and gain evidence they themselves could incontrovertibly trust. Police and criminal investigations could do that too.

You could kill people, with no ill will, just in order to live through their experiences. Famous people, highly interesting people, people with widely publicised life-stories—all would become susceptible to this. Life tourism, essentially, where the ticket price is one bullet. This would be illegal, of course, but who wouldn’t give up the chance to live the life of the Queen?

You want to know what it’s like to be John F. Kennedy? You can! Just kill him. Well, you can’t, because Lee Harvey Oswald did that already, so you’d have to kill him instead. Or actually, Jack Ruby, who killed Oswald. Just add yourself to the end of the killing chain, and eventually, after living through the lives of the intermediaries, you’ll get to Kennedy, the main attraction.

(But you can’t. Jack Ruby died of a pulmonary embolism in prison in 1967, so the chain ends there and Kennedy’s life-experiences are forever lost.)

Your mother is on her deathbed. “Kill me,” she could say, “right before the end. Kill me, as I killed my mother before me, and she killed her mother before her, all the way back through the mists of time to the beginning of memory. This is the only way you can live the family story and keep it alive. The potassium chloride is in the second drawer from the right. I love you.” You’ve never wanted to kill anybody in your life, least of all your dear old mum, but you’re the eldest daughter and she’s chosen you to pass her life onto. What do you do?

There’s a stranger in your bedroom, and you notice, by the glint of moonlight through the window, the gun in her hand. She raises it directly at you. “Wait, no, who are you, don’t shoot—” you cry, but you’re too late. The blast, the searing pain, the world shifting out of place, and suddenly you’re her, lowering your handgun as the billionaire’s blood dries on the bed-sheets. That’s not what’s supposed to happen, was it? The killer lives the victim’s life, not the other way around, right? But then you realise. You were Emily all along. All of Mr. Jennings’ life, which you just experienced, was merely a replay for you. You were always Emily. Unless, of course, you were originally someone else.

The premise breaks down in interesting ways at the seams.

What if you kill yourself? Plenty of people do. (In fact, the incentives for committing suicide are stronger in this world: if you harbour a secret you intend to take to the grave, it’s a way to ensure that nobody else gets to live your life and discover it.) Do you live your life over and over again, forever? By the rules we’ve set, I think you’d only repeat your life once, and that’s it.

What if two people kill each other at the same time? If Dottie expired a few seconds later than Carlyle, would she get to live out his life (and then the last few seconds of her own) while he just dies and experiences nothing? If they passed at the exact same instant, would they live each other’s lives?

What if multiple people kill the same victim? Would they all get to live out her life? Or only the killer who participated “most” in the killing, the one who struck the fatal blow, fired the fatal bullet?

What even counts as a killing? If a drunk knocks over a gas lamp and three patrons fail to escape as the saloon goes up in flames, did he kill them? If an engineer installs a faulty bolt that precipitates a highway collapse a few years later and twenty bodies are found amid the rubble, did she kill them? How do we assign blame for a death? (This is very much a question for the real world too.)

Do animals participate in this phenomenon? Do wildlife hunters live the lives of deer every time they kill one? Do you live a few weeks of ant life every time you step on an ant? How far down the food chain does this go? What if for every second of your human life, you also must live cumulative billions of years as amoebae?

This extreme is probably where the premise fails to be a compelling narrative device. But I bet that some writer, far more skilled than I am, has probably already taken something like this and turned it into a novel.