I'm not the person you replied to, but is this supposed to be a gotcha? I assume the answer would be zero. But if you accept that the criminal justice system makes mistakes (between 100k-200k in current prison population per https://link.springer.com/article/10.1007/s10940-018-9381-1) then it's obvious it's better to be able to have reversible punishments. Unless you are suggestion the complete abolition of incarceration for all crimes?

I suppose what I'm rejecting is the dichotomy between imprisonment being "reversible" and execution being "irreversible." Neither are reversible, of course. You can't give someone back the time they were unjustly imprisoned.

I think the reversibility argument is a sloppy way of trying to say that there is some massive difference in kind between a lifetime of imprisonment and an execution. The argument seems to be implying that outright ending a human life is taking infinite value, but imprisoning someone for an entire lifespan is taking only finite value. That's the only way it would make sense to allow for the possibility of some erroneous lifetime imprisonments, but not allow for the possibility of some erroneous executions.

First, you relying too much on semantics. "Reversible" is understood to be "I can reverse taking away someone's freedom". They were in prison, but now they are not. You can't give back the lost time, and everyone understands that. Also, it comes from "reversing a conviction" which is a legal term.

Secondly, and I'm sorry, but your characterization is incredibly sloppy. The overall outcome is better if even one exoneration happens and you assume equal preference for life imprisonment vs execution. However:

* Many wrongful convictions will be exonerated. There are multiple per year. There has been at least one this year: https://deathpenaltyinfo.org/innocence-cases#CliffordWilliam...

* Further, while the preference might not be "infinite" you can just look at the overwhelming majority - innocent or not - of death row prisoners that exhaust all avenues of appeal to see that there is a strong preference there.

First, I don’t think I’m playing semantic tricks. The finality of imprisonment and execution are the same. You don’t get time back if you’re released from prison. The difference is that you’re still alive, but of course that’s already the difference between imprisonment and execution. The fact that the death penalty involves killing someone is just definitional, it’s not a justification for why the death penalty is bad.

Secondly, of course I don’t dispute that there’s generally a preference for life imprisonment over execution.

The finality of eating an apple is the same if you are an external observer and just judging it by the direction of the time arrow.

From the perspective of the - potentially falsely - accused, "The difference is that you’re still alive" is a pretty fundamental distinction and "The finality of imprisonment and execution are the same" is false.