At Princeton on Monday, Justice Antonin Scalia defended his writings on homosexuality — by comparing disapproving of homosexuality to disapproving of murder.

Scalia was asked by a gay student why he equates laws banning sodomy with those barring bestiality and murder.
“I don’t think it’s necessary, but I think it’s effective,” Scalia said, adding that legislative bodies can ban what they believe to be immoral. …
“It’s a form of argument that I thought you would have known, which is called the ‘reduction to the absurd,’ ” Scalia told [freshman Duncan] Hosie of San Francisco during the question-and-answer period. “If we cannot have moral feelings against homosexuality, can we have it against murder? Can we have it against other things?”
Scalia said he is not equating sodomy with murder but drawing a parallel between the bans on both.
Then he deadpanned: “I’m surprised you aren’t persuaded.”

Ah, the reductio ad absurdum, which stretches any given argument to its ridiculous limit. It’s a frequent tool of gay-marriage opponents. This is the argument style that has given us such great gifts as the line of thinking that goes, “But if we allow gay marriage, we’ll have to let people marry dogs and robots! Where can you draw the line?”

And inevitably, we respond, “Before dogs and robots.”

This always happens. And it’s easy to see why. A majority of young people support gay marriage. A majority of people in general find gay relations acceptable, according to Gallup. The reason opponents have to start dragging dogs and robots and polygamy into the equation is because most people do not have moral feelings against homosexuality. If we did, all Scalia would have to say is that “if we start approving of gay marriage, we’ll have to let men marry each other!” and we would all cry “Shame! Shame!” but this no longer happens. The arc of history is long and bends away from that. And so he has to say things like, “Well, if we start approving of gay marriage, we’ll lose our ability to disapprove of MURDER!” And instead of making us feel ridiculous, we start worrying that he has a giant stash of snuff films under his robe.

It’s not that we don’t understand what you’re doing philosophically when you make such arguments. It’s just that — well, the only thing reduced to absurdity by your argument is you.

In this case, Scalia is right: you can have moral feelings about anything. You can have moral feelings about murder. He can have moral feelings about homosexuality. I can have moral feelings about people who read “50 Shades of Grey” too close to me on the bus. We can have moral feelings about all sorts of things, and, thanks to our right to freedom of assembly, we can even get together with people who share those moral feelings and, say, sing hymns or walk around with signs expressing our disapproval. There are so many fun things we can do with moral feelings.

But enshrining them in law is a different standard. There are all sorts of things I disapprove of personally, and I appreciate very much my right to do so, but I understand that my moral feelings about them are not the basis by which we should make laws. Personal morality and public morality are two different things. Just because there is no law against something doesn’t mean I am not free to find it wrong. If laws were just opportunities for me to enshrine my moral feelings, there’d be a ban on comma splices.

And I’m not sure about his analogy. “Murder is always a mistake,” Oscar Wilde wrote. “One should never do anything that one cannot talk about after dinner.” And we know how he felt about the other subject.