Cruel though it may sound, we must see to it that the patient's suffering, to a degree that is in some way or other effective, does not come to an end prematurely. If, owing to the symptoms having been taken apart and having lost their value, his suffering becomes mitigated, we must re-instate it elsewhere in the form of some appreciable privation; otherwise we run the danger of never achieving any improvements except quite insignificant and transitory ones

Freud (1919) Lines of Advance in Psycho-Analytic Therapy. cited in: Jürgen Habermas (1972) Knowledge and Human Interests. p. 234