You know the old urban legend about the lonely college girl, the dog, and the jar of peanut butter?  Well, I’m here to tell you, it’s all good!   So says superstar philosopher Peter Singer (in the world of professional philosophers, an appearance on “60 Minutes” earns you superstar status).

A few weeks ago I went to hear Singer – the Australian bioethicist who became famous in 1975 for his book “Animal Liberation” – speak on the UC Berkeley campus.

The book became a touchstone for the animal rights movement, and the catchy name found its way into groups like the Animal Liberation Front and the Earth Liberation Front.

Put broadly, it’s wrong, Singer argues, for one animal to make another suffer.  Singer is a utilitarian, and adheres to the view that we should make our choices based on what creates the greatest good for the greatest number, regardless of how many legs or tails that number has.

So how can he say that boinking animals is OK?  

Sit tight – we’ll get there.

I arrived half an hour early at the lecture hall of the Alumni House, and it quickly filled to capacity with a mix of academics, students and whatever dregs like myself noticed the little ad for the free lecture in our local weekly.

It was a polite, urbane crowd, the type that chuckled when Singer remarked, when the lights in the room flickered briefly, that if anyone wanted to leave, they needn’t sabotage the electrical system.

It was a charming line.

After the end of the hour long lecture, Singer took questions, and here is where things went from kind of interesting to really interesting.

A dozen or so people lined up in front of a microphone.

Half of them thanked Singer for turning them into vegetarians, and then followed up with smart, perceptive questions I can’t remember, but I do remember the questions asked by two young men who appeared to be grad students in their mid-20’s.

The first asked, with a completely straight face, if bestiality was morally acceptable.

No one tittered.   No one offered anecdotes involving lonely Scottish shepherds.

One thing I learned in that lecture hall was that the second best way to test the integrity of a utilitarian (the first best being to throw a live grenade at him and see if he jumps on it to save a dozen professors and students he has barely met)…

…is to take an idea to its extreme.

So why not look at the morality of boinking animals?

Singer thought about it briefly, then said that if the animal was a willing participant, ie, the sex was consensual, and there was no unwanted pain involved, then yes, of course humans going doggy style on dogs, goats, what have you, is fine.  No suffering, no harm: therefore no foul.  Break out the peanut butter.  Simple as that.

The second young man asked if it was okay to kill and eat animals, if, in an ideal world, they were raised humanely and killed painlessly.

Singer seemed to struggle a bit more with this one.

“I suppose,” he said, “if the animal had no ability to remember or anticipate, it would be ethical.”  Someone in the audience yelled out “what about fish?” and Singer said he supposed it would be okay, with one caveat.

That caveat would be figuring out how to figure out whether the fish would “miss” being alive, which means it would need to have the capacity for memory and imagination to have the conscious desire to keep living.

“Now I know of studies of cows,” he added, “even those raised humanely and allowed to roam freely, who, when their calves are taken from them, return to the same spot for weeks looking for their missing child.”  The “missing” of its calf, he reasoned, made killing a cow wrong.  It would prefer to have its child live, and could imagine its past and future – and suffer, unlike – perhaps – a fish.

But again, we need an accurate, reliable way to figure out what’s going on in fishy’s mind.

As the line was winding down, a third person, a middle aged woman, took the mic and asked what Singer’s own “threshold number” would be for sacrificing his own life to save others.  This reminded me of drunken late night dorm talk: “If you killed yourself right now, bro, and it saved 2 million people, would you do it?  How about 200,000?  20,000?  2?”

In other words, the grenade question.

The woman skipped drunken dorm nuances like, “But wait, dude, what if those two people were like people you hated?  Or, what if you had to kill someone else, like with your own bare hands, but that would save, like, 5 other people?”

Singer, answering the woman’s question, said, “In theory, I hope it’s two – two is more than one, therefore I should pull the trigger – but I hope I’m not asked to prove it.”

That’s when he won me over.