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The Phony Contraception Argument

The opposition to contraception has, as I said, no scriptural basis. Pope Pius XI once said that it did, citing in his encyclical Casti Connubii (1930) the condemnation of Onan for “spilling his seed” rather than impregnating a woman (Genesis 38.9). But later popes had to back off from this claim, since everyone agrees now that Onan’s sin was not carrying out his duty to give his brother an heir (Deuteronomy 25.5-6). Then the “natural law” was fallen back on, saying that the natural purpose of sex is procreation, and any use of it for other purposes is “unnatural.” But a primary natural purpose does not of necessity exclude ancillary advantages. The purpose of eating is to sustain life, but that does not make all eating that is not necessary to subsistence “unnatural.” One can eat, beyond the bare minimum to exist, to express fellowship, as one can have sex, beyond the begetting of a child with each act, to express love.

The Roman authorities would not have fallen for such a silly argument but for a deep historical disrelish for sex itself. Early Fathers and medieval theologians considered sex unworthy when not actually sinful. That is why virgin saints and celibate priests were prized above married couples. Thomas Aquinas said that priests must not be married, since “those in holy orders handle the sacred vessels and the sacrament itself, and therefore it is proper (decens) that they preserve, by abstinences, a body undefiled (munditia corporalis) (Summa Theologiae, Part 3 Supplement, Question 53, article 3, Response). Marriage, you see, makes for defilement (immunditia). The ban on contraception is a hangover from the period when the body itself was considered unclean, as Peter Brown overwhelmingly proved in The Body and Society (1988).

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