Full Idea
The purposes of punishment include deterrence, prevention, rehabilitation, and retribution, but they don't always sit well together. Deterrence is best served by making prisons miserable places, but this may run counter to rehabilitation.
Clarification
'Retribution' is revenge
Gist of Idea
Deterrence, prevention, rehabilitation and retribution can come into conflict in punishments
Source
Robert Fogelin (Walking the Tightrope of Reason [2003], Ch.2)
Book Reference
Fogelin,Robert: 'Walking the Tightrope of Reason' [OUP 2004], p.62
A Reaction
It seems to most educated people that retribution should be pushed far down the list if we are to be civilised (see Idea 1659), and yet personal revenge for a small act of aggression seems basic, normal and acceptable. We dream of rehabilitation.
Related Idea
Idea 1659 Protagoras seems to have made the huge move of separating punishment from revenge [Protagoras, by Vlastos]