The utility that people gain from money is not linear (and the utility that people lose when losing $X worth of organs is really not linear). Making it possible to extort $100000 from someone who has a lot of money, then, causes less of a loss in utility to them than making it possible to extort $100000 from someone who would have to sell his organs to get the money.
It is easier, in general, to extort a poor person for $X than a rich person for the same amount, for hopefully obvious reasons. For instance, the poor person can’t hire a private detective, bribe the police, or use his connections to track down the kidnapper, and the kidnapping is much less likely to make the national news. And it is much less likely that when you kidnap his kids you piss off some very important people.
It is easy for the kidnapper to figure out that someone has organs. It is harder for the kidnapper to figure out that they have $100000 in a bank account (unless they are rich enough to fall into category 2) or that they can feasibly mortgage their house within a short time.
The market price for organs is not that high compared to how much the person would lose in utility from losing the organs. So a more plausible scenario is that the kidnapper asks for $10000, which is the sale price of the organs, but the person with the organs loses the utility that he would lose from losing $1000000 in cash. If the kidnapper instead extorted someone who had money, they would not lose as much utility.
That’s a fully general argument against having any capabilities.
No, it’s not, for several reasons:
The utility that people gain from money is not linear (and the utility that people lose when losing $X worth of organs is really not linear). Making it possible to extort $100000 from someone who has a lot of money, then, causes less of a loss in utility to them than making it possible to extort $100000 from someone who would have to sell his organs to get the money.
It is easier, in general, to extort a poor person for $X than a rich person for the same amount, for hopefully obvious reasons. For instance, the poor person can’t hire a private detective, bribe the police, or use his connections to track down the kidnapper, and the kidnapping is much less likely to make the national news. And it is much less likely that when you kidnap his kids you piss off some very important people.
It is easy for the kidnapper to figure out that someone has organs. It is harder for the kidnapper to figure out that they have $100000 in a bank account (unless they are rich enough to fall into category 2) or that they can feasibly mortgage their house within a short time.
The market price for organs is not that high compared to how much the person would lose in utility from losing the organs. So a more plausible scenario is that the kidnapper asks for $10000, which is the sale price of the organs, but the person with the organs loses the utility that he would lose from losing $1000000 in cash. If the kidnapper instead extorted someone who had money, they would not lose as much utility.