"... [marriage] is a human good. Its goodness stands upon, and flows out of, what we are as human beings. It is good to unite with another person in a comprehensive union. It is good for that union to be of the sort that uniquely completes the one biological function that depends on two persons, male and female. It is good for that union to be of the sort that can and usually does result in offspring, the effusive fruit of the couple’s love. It is good for those children to be raised by their biological parents. It is good for individuals, for couples, for children, for society as a whole, which by the way is the only reason it makes sense for government to be involved in marriage. It is not good to practice or propose any view of marriage that would undermine these goods, just because they are real goods.
They are good because of who we are as humans. And it is our humanity, not any three authors’ opinions, or any religious or conservative political group’s viewpoint, that is the immovable object against which the (seemingly) irresistible force of same-sex “marriage” is pressing itself. There is, after all, an answer to the question, “what is marriage?” In its core (not its accidents but its substance), that answer has been the same the world over in virtually all cultures: a fact which is easily understood in virtue of humans being humans in all cultures the world over."