The Catholic church is wrong about human sexuality—just like it was wrong about the movement of the planets. Persecuting Galileo in the 16th Century didn't make the church right then and persecuting Catholic nuns in the 21st Century doesn't make the church right now.
Let's also remember that sex and the movement of the planets aren't the only things the Catholic church has gotten wrong:
In the 17th century, based on a question raised by the Bishop of Quebec, the Roman Catholic Church ruled that the beaver was a fish (beaver flesh was a part of the indigenous peoples' diet, prior to the Europeans' arrival) for purposes of dietary law. Therefore, the general prohibition on the consumption of meat on Fridays during Lent did not apply to beaver meat. The legal basis for the decision probably rests with the Summa Theologica of Thomas Aquinas, which bases animal classification as much on habit as anatomy. This is similar to the Church's classification of the capybara, another semi-aquatic rodent.
And there was this:
In the late 19th and 20th centuries women began to struggle to win the vote, civil and political rights, higher education and access to professional employment. Catholicism was hostile to feminism, arguing in the 1920s against women’s suffrage. Women’s place was in the home, Catholic bishops argued, and their female nature would be debased by such rough masculine activities as voting. In 1930 Pope Pius XI condemned women’s emancipation as undermining the divinely founded obedience of the wife to her husband and a false deflection from her true and sole role as mother and homemaker.
And what else... oh, yeah. Slavery.
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