God said "It is not good for the man to live alone. I will make a suitable companion to help him." And so God gave to Adam animals of all kinds, and yet "not one of them was a suitable companion to help him. . . "
"Then the LORD God made the man fall into a deep sleep, and while he was sleeping, he took out one of the man's ribs and closed up the flesh. He formed a woman out of the rib and brought her to him."
"Then the man said, "At last, here is one of my own kind--Bone taken from my bone, and flesh from my flesh. 'Woman' is her name because she was taken out of man." (Gen. 2:18, 20-23 TEV)
Because only another human being shares equal status with another human being, only two persons can truly become "partners" in activity with one another. JPII says that "a person is for another person the source of experiences with a special emotional-affective charge" (32-3). The depths of personal and moral interaction that are possible between two persons bring with it great potential for pleasure as well as pain, emotionally, physically, psychologically, and spiritually. When we throw romantic relationships into the mix, the potential for pleasure and/or pain is something I'm sure we all can relate to.
Peter Kreeft, in his book Catholic Christianity makes a comment regarding "Social and Economic Morality" that is quite applicable to the issue of pleasure in human relationships. He writes:
"Profit is to production what pleasure is to sex: right and proper and natural when associated with the intrinsic purpose of the activity, but all too easily divorced from that purpose and loved for its own sake" (264).
JPII makes the same point in Love & Responsibility regarding the temptation for man and woman to make pleasure the "say all and be all" in their relationships with one another. He writes in his usual eloquent, philosophical style:
"For man, precisely because he has the power to reason, can, in his actions, not only clearly distinguish pleasure from its opposite [pain], but can also isolate it, so to speak, and treat it as a distinct aim of his activity. His actions are then shaped only with a view to the pleasure he wishes to obtain, or the pain he wishes to avoid. If actions involving a person of the opposite sex are shaped exclusively or primarily with this in view, then that person will become only the means to an end" (33).
After the fall, it has become an enormous temptation for us to use one another for the sake of physical and/or emotional pleasure. JPII says "enjoyment must be subordinated to love" (34). He warns us again that sometimes "use" masquerades as "love"; selfishness often justifies itself as being love.
The utilitarian principle is that pleasure in itself is "the sole or at any rate the greatest good, to which everything else in the activity of an individual or a society should be subordinated" (36). Of course, people want to avoid pain and experience pleasure by nature, but pleasure is an elusive thing; it is contingent and incidental, not something we can secure by our actions. In fact, we cannot even properly predict the degree of pain that may be entailed in our various actions. Obviously, pain and pleasure cannot be our measuring stick for the morality or worthiness of our actions.
Man is a rational being; he is a material and spiritual entity with his soul being the animating force of his human existence. It is, therefore, improper for man to organize his actions around the principle of avoiding pain and seeking to maximize pleasure.*
Because JPII says it best, I'm going to close with his thoughts:
". . . Pleasure (as opposed to pain) cannot be the only factor affecting my decision to act or not to act, still less the criterion by which I pronounce judgment on what is good and what is bad in my own or another person's actions. Quite obviously, that which is truly good, that which morality and conscience bid me do, often involves some measure of pain and requires the renunciation of some pleasure. The pain involved, or the pleasure which I must forego, is not the decisive consideration if I am to act rationally. What is more, it is not fully identifiable beforehand. Pleasure and pain are always connected with a concrete action, so that it is not possible to anticipate them precisely, let alone to plan for them or, as the utilitarians would have us do, even compute them in advance. Pleasure is, after all, a somewhat elusive thing" (36).
* This is not the case when it comes to eternal pain and eternal pleasure. We should rather endure temporal pain, on earth or in purgatory, in order to obtain the joy of being in God's presence forever and to avoid the eternal torment of separation from God in hell. That is proper to the nature and design of the human person.