In spite of its intentions, what John Paul II calls “sexual puritanism” or “rigorism” ends up cozy with utilitarianism, the notion that persons can be used as means to achieve certain egocentric ends (Love and Responsibility).
According to the “puritanical” view, “the Creator Himself uses persons as means to [the end of existence of the species]. It follows that conjugal life and sexual intercourse are good only because they serve the purpose of procreation. A man therefore does well when he uses a woman as the indispensable means of obtaining posterity. The use of a person for the objective end is the very essence of marriage. To use in this way is a good thing.” But it is wrong to seek pleasure in the process of procreation: “Although it is indissociable from use in the first sense it is an intrinsically impure element, a sort of necessary evil. That evil must, however, be tolerated since there is no way of eliminating it” (59).
The problem is in the separation of “use for enjoyment” from the approved “use for procreation.”
The rigorist condemns “use for enjoyment,” but the fact that it is isolated as a distinct end brings it close to a utilitarian understanding of use: “rigorism strives to overcome in practice what it has completely accepted on theoretical grounds” (60).
The solution is to see procreation and sexual enjoyment as unified aspects of sexuality: “There exists a joy which is consonant both with the nature of the sexual urge and with the dignity of human persons, a joy which results from collaboration, from mutual understanding and the harmonious realization of jointly chosen aims, in the broad field of action which is love between man and woman. This joy, this frui may be bestowed either by the great variety of pleasures connected with differences of sex, or by the sexual enjoyment which conjugal relations can bring. The Creator designed this joy, and linked it with love between man and woman in so far as that love develops on the basis of the sexual urge in a normal manner, in other words, in a manner worthy of human persons” (60-61).