Having described punishment as “pain intended as pain”, Christie continues in the preface:
“None of the attempts to cope with the intended pain seems, however, to be quite satisfactory. Attempts to change the law-breaker create problems of justice. Attempts to inflict only a just measure of pain create rigid systems insensitive to individual needs. It is as if societies in their struggle with penal theories and practices oscillate between attempts to solve some unsolvable dilemmas.
My own view is that the time is now ripe to bring these oscillatory moves to an end by describing their futility and by taking a moral stand in favour of creating severe restrictions on the use of man-made pain as a means of social control. On the basis of experience from social systems with a minimal use of pain, some general conditions for a low level of pain infliction are extracted.” (emphasis added)
Full text at https://www.prisonpolicy.org/scans/limits_to_pain/