The reformative effect of punishment is a belief that dies hard, chiefly I think, because it is so satisfying to our sadistic impulses.
A Sunday school is a prison in which children do penance for the evil conscience of their parents.
It isn't true that convicts live like animals: animals have more room to move around.
Prison, dungeons, blessed places where evil is impossible because they are the crossroads of all the evil in the world. One cannot commit evil in hell.