Although the pleasure derived from the satisfaction of genuine physiological needs and of irrational psychic needs consists in the relief from tension, the quality of the pleasure differs significantly. The physiologically conditioned desires such as hunger, thirst, and so on, are satisfied with the removal of the physiologically conditioned tension, and they reappear only when the physiological need arises again; they are thus rhythmic in nature. The irrational desires, in contrast, are insatiable. The desire of the envious, the possessive, the sadistic person does not disappear with its satisfaction, except perhaps momentarily. It is in the very nature of these irrational desires that they can not be “satisfied.” They spring from a dissatisfaction within oneself. The lack of productiveness and the resulting powerlessness and fear are the root of these passionate cravings and irrational desires. Even if man could satisfy all his wishes for power and destruction, it would not change his fear and loneliness, and thus the tension would remain. The blessing of imagination turns into a curse; since a person does not find himself relieved from his fears, he imagines ever-increasing satisfactions would cure his greed and restore his inner balance. But greed is a bottomless pit, and the idea of the relief derived from its satisfaction is a mirage. Greed, indeed, is not, as is so often assumed, rooted in man’s animal nature but in his mind and imagination.
We have seen that the pleasures derived from the fulfillment of physiological needs and neurotic desires are the result of the removal of painful tension. But while those in the first category are really satisfying, are normal, and are a condition for happiness, those in the latter are at best only a temporary mitigation of need, an indication of pathological functioning and of fundamental unhappiness. I propose to call the pleasure derived from the fulfillment of irrational desires “irrational pleasure” in contradistinction to “satisfaction,” which is the fulfillment of normal physiological desires.
Erich Fromm (1947) Man for Himself: An Inquiry into the Psychology of Ethics. p.188-189.