If you go to a party, and the next morning you’ve forgotten the entire night, has anybody died?
Seems like a silly question, doesn’t it?
What if before the party, you take a drug that causes amnesia? This time, you know in advance that you’ll forget the party after it’s over. When you take the drug, do you feel like you’re killing yourself?
I’m betting your answer hasn’t changed, so let’s make things a little more interesting. This time, we first make a perfect copy of you (it doesn’t matter how; let’s say a magic spell). One copy takes a pill that causes a dreamless sleep, and the other takes the memory-loss pill and then goes to the party.
Both copies would wake up feeling exactly the same (let’s say the spell also makes them immune to hangovers), with no memory of the night before. If the pills both look the same and we moved you to different beds while you were asleep, you wouldn’t even know which copy you were upon waking; both sets of memories would be identical.
With me so far? All right, here’s the twist: one of the pills was fatal. One copy wakes up, the other never does.
Is that death?
The obvious answer, of course, is yes: before the party there are two beating hearts, the next morning there’s only one, and since 2 > 1 someone must have died. But the obvious answer isn’t always the correct one–a beating heart isn’t what we really value!
Human life is what we value. What if some incredible future technology allows people to survive without a heart? Or without any body at all? How will we decide what “death” is, when biology becomes unnecessary? Would that future method say that, in fact, no one has died in the final version of our thought experiment?
The obvious answer isn’t always wrong, either–it sure feels like something has been lost when your clone never wakes up. But what, exactly?
I’ll post a follow-up that proposes an answer to that question, but while you mull over your own answer here are a few other nuggets to chew on:
- Imagine that after the copy has died, we make another copy of the survivor and switch that one out for the dead one. Now the end result is indistinguishable from a version where neither pill was fatal and both copies live–if nobody told you, you would never even know which version you’d experienced! Has there still been a death?
- Would you be hesitant to take the pill, knowing there’s a 50/50 chance you’ll die? Would you still be hesitant in the variation where the survivor gets copied again?
- What if someone offered to pay the surviving copy a million dollars if you both take the pill, but if either of you refuse you get nothing? Would taking the pill be worth it then?
- What if they offered a billion dollars? How much would be enough?
- If the clone’s death is bad because their existence was valuable in itself, would three clones be even better? If not, how can something valuable be lost without first being created? If yes, how many copies is too many? Should we clone everyone?
- What if it isn’t clones–what if each new person is unique? Would it be good to create as many people as possible? How many is “as many as possible?” Is a trillion people leading lives barely worth living, better than a million leading lives of joy and fulfillment? If the latter is better, would just one person leading the best life possible be better still? If more people isn’t always good, what makes death bad?
