"Punishment has something in common with forgiveness, as it tends to put a limit on something that without intervention could continue indefinitely." --Hannah Arendt, cited by Derrida as arguing that one cannot forgive what one cannot punish, or punish what is unforgivable.
Compare with the point from Nozick (or at least that's where I read it): that punishment is a derivative way of bringing someone's line in life with, and responsive to, correct values...
