SF author John C. Wright has yet another interesting post on morality.
Back when I was a fun-loving, God-hating atheist, logic forced me to the conclusion that the passions of man, including sexual passions, were destructive of happiness and life unless conformed into the boundaries of reality.
My conclusions can be summed as follows. I do not give each step of the logic here, due to space limitations, but a disinterested reader can flesh out the enthymemes with common sense:
And then he lays out how "cold reason" brought him to this conclusion.
Later in posts he references a letter he wrote to a Christian friend of his that had said that the overwhelming majority opinion approved of fornication and adultery where with the help of CS Lewis gives an imaginary trial of history.