Obviously the optimal number of rapes is 0, but the optimal amount of rapes we should try to prevent is not infinite, and thus the optimal amount of rapes we accept as a consequence of the above policy is non-zero.
It's really a simple cost-benefit calculation; the cost of preventing the last 0.1% rape on earth is surveillance cameras in every home and egregious violations of privacy, obviously the cost of such a scheme is probably not worth it.
The simple observation is that there are tradeoffs: in exchange of preventing <bad thing>, we have to give up <good thing>, at some sort non-linear curve. The cost of rape prevention goes up with each rape prevented, there reaches a point where the cost is no longer worth it and we should call it a day.
People can (and do) argue all day about the point where the marginal cost of rape prevention is too great, but I'm fairly certain most would agree that it's not infinite.
It's really a simple cost-benefit calculation; the cost of preventing the last 0.1% rape on earth is surveillance cameras in every home and egregious violations of privacy, obviously the cost of such a scheme is probably not worth it.
The simple observation is that there are tradeoffs: in exchange of preventing <bad thing>, we have to give up <good thing>, at some sort non-linear curve. The cost of rape prevention goes up with each rape prevented, there reaches a point where the cost is no longer worth it and we should call it a day.
People can (and do) argue all day about the point where the marginal cost of rape prevention is too great, but I'm fairly certain most would agree that it's not infinite.