For Nietzche, "pain is the most powerful aid to mnemonics." "Man could never do without blood, torture, and sacrifices when he felt the need to create a memory for himself." "If something is to stay in the memory, it must be burned in: only that which never ceases to hurt stays in the memory." (Genealogy of Morals, Ecce Homo)
On the other hand, ritual may be seen as a way to keep memory alive without the experience of pain. Bataille echoes Nietzche's description of the role of religious sacrifice. He describes sacredness as the revelation of continuity through the death of a discontinuous being to those who watch it as a solemn rite. (p.22)
"Those who do not feel pain seldom think that it is felt." Samuel Johnson. "To have pain is to have certainty , to hear about pain is to have doubt." (Elaine Scarry, The Body in Pain, p. 13)
Like consciousness, pain as a philosophical issue raises the questions of subjectivity and of other minds. Wittgenstein rejected the classical status of pain as the paradigm of direct intuition. When one is in pain, he said in the Philosophical Investigations, one cannot say, except perhaps as a joke, that one knows one is in pain. Say that one cannot doubt it and leave it at that, he suggested.
According to Scarry, physical pain is language destroying. It is monolithically consistent in its assault on language. The body provides a point of mediation between what is perceived as purely internal and accessible only to the subject and what is external and publicly observable. (see qualia )
One of Bill Clinton's greatest political assets was his convincing claim "I feel your pain." Republicans punished him by drawing public attention to his pleasures. But even if Clinton's expressions of sympathy could not really be true, they did seem to make people feel better.
"The sense of pain is a consequence of brain mechansims that establish awareness of the existence of the body; the body, not a sense of absolute space, is the brain's absolute frame of reference." (Rosenfeld, The Strange, Familiar and Forgotten, p.45) See also body image.
Henri Bergson describes affective states, more or less vaguely localized, as intermediate states between images and ideas. According to Bergson, there is hardly any perception which may not, by the increase of the action of its object upon our body, becaome an affection, and more particularly, pain. (p.53) Every pain is a local effort.
The pain of phantom limbs is a particulary perplexing phenomenon. The pain is as real as pain can be, yet the presumed source of the pain is absent.