Forty years ago, on July 25, 1968, Pope Paul VI issued his long-awaited encyclical on contraception, ‘‘Humanae Vitae.’’ Based on a rich understanding of sexuality as inseparably embodying both unitive and procreative dimensions, it reiterated the Catholic Church’s condemnation of “any action which either before, at the moment of, or after sexual intercourse, is specifically intended to prevent procreation--whether as an end or as a means.” Yes to love, marriage and openness to children. No to the condom, the pill, and hedonism. All hell broke out in consequence.

It was the height of the sexual revolution of the 1960s, principally marked by the separation of sex from childbearing. The birth control pill and the condom and other techniques of artificial contraception like the IUD made it seemingly possible to pursue sexual gratification without consequences. Sex was disassociated from procreation, and so began the simultaneous trivialization and obsession with sex that still plagues us.

Things weren’t always so in the days before condom was king. Sounding like St. Augustine or St. Thomas Aquinas on this matter, even the atheist psychologist Sigmund Freud had written, “It is a characteristic common to all perversions that in them reproduction is put aside as an aim. This is actually the criterion by which we judge whether a sexual activity is perverse--it departs from reproduction as its aim and pursues the attainment of gratification independently.”

All Christian denominations had agreed that contraception was immoral, at least until the Lambeth Conference in the 1930s marked the first breach in the wall, with the Anglican Church then beginning to allow contraception. The Washington Post at that time editorialized against the change in moral teaching, warning that it “would sound the death knell of marriage as a holy institution by establishing degrading practices which would encourage indiscriminate immorality.” (I am grateful to Phil Lawler for these references.)

I was 17 in the summer of 1968, about to enter my senior year in high school in Washington, D.C., the second oldest of 13 children, the youngest of whom had just been born. (The culture of contraception had not come to my parents, thank God.) I do remember that one of our parish priests got up in the pulpit to denounce the pope’s teaching at the time, for which Cardinal O’Boyle, the archbishop of Washington, suspended him from his priestly faculties along with other priests who had publicly defied the pope’s teaching. I believe that priest ended up leaving the Church, getting married, and becoming an Episcopalian; the Anglicans, as we have seen, were more hospitable to contraception. The Washington Post, having changed sides in the culture war, then vilified the courageous cardinal because he held fast to what the Church had always taught, and still teaches.

The sexual revolution continued, in spite of the pope’s warnings. Pope Paul VI had predicted the consequences: “How easily this course of action could open wide the way for marital infidelity and a general lowering of moral standards. ... Another effect that gives cause for alarm is that a man who grows accustomed to the use of contraceptive methods may forget the reverence due to a woman, and, disregarding her physical and emotional equilibrium, reduce her to being a mere instrument for the satisfaction of his own desires, no longer considering her as his partner whom he should surround with care and affection.”

One wonders: Would we have such widespread acceptance of abortion, divorce, infidelity, the birth dearth (or population implosion) in developed countries, homosexual practices, Internet pornography, mistreatment of women, sexual abuse of children, and other indicia of a “general lowering of moral standards” had people accepted and tried to live the Church’s teaching on openness to life rather than ignore and defy it? For that matter, would the Anglican Church, again gathered at Lambeth, now be debating whether to recognize a practicing homosexual bishop if it hadn’t made the turn it did when it first accepted contraception? Could it be that, once you separate sex from procreation, practically anything goes?

In Sydney on July 20, at the concluding Mass of World Youth Day, Pope Benedict XVI offered a competing view: “Empowered by the Spirit, and drawing upon faith’s rich vision, a new generation of Christians is being called to help build a world in which God’s gift of life is welcomed, respected and cherished--not rejected, feared as a threat and destroyed. A new age in which love is not greedy or self-seeking, but pure, faithful and genuinely free, open to others, respectful of their dignity, seeking their good, radiating joy and beauty. A new age in which hope liberates us from the shallowness, apathy and self-absorption which deaden our souls and poison our relationships.”

Dwight G. Duncan is a professor at Southern New England School of Law. He holds degrees in both civil and canon law.