You encourage the abolition of experimentation on animals for both ethical and practical reasons. But when a cure for some minor ailment is found after decades of research on thousands of animals, I think the general public considers that money and those animals’ lives — no matter how many thousands — well spent.

Let me be clear about what PCRM’s mission is. We promote preventative medicine, which mostly involves exercise and diet. There is abundant evidence that the healthiest diets are those that avoid animal products — among other changes you would want to make, like avoiding fried foods. In addition, we conduct research trials and have been active in research for a long time. Like most medical organizations, our efforts and research do have an ethical foundation. Where the participants in research are human beings, we have advocated the highest ethical standards.

We have actually sued the federal government over an experiment that involved injecting short children with a genetically engineered growth hormone, which these kids did not need. We don’t object to kids’ getting a hormone if their bodies are not making it. But these were kids with adequate growth hormone levels, and the experimenters were trying to alter their physiology through injections, and it was fraught with danger.

When the research participants are animals, it is quite apparent that society has turned a blind eye to extraordinary suffering. But society in general is starting to recognize that animals are not blocks of wood or glassware and that they have the capacity to suffer.

Over and above that, it makes your research that much better if your results don’t have to jump the gap from animal to human. When I pick up the Journal of the American Medical Association, or the other leading medical journals, I don’t see articles titled “Rat Cured.” That is not what the rank and file of American physicians want to know about. I’m not suggesting that the average physician is ready to march in the street for animals. I’m suggesting that they’re interested in what will work for their human patients.

There is no question that results from ethical research conducted on human populations are miles ahead of results from research conducted on animals. And if we aren’t recognizing that there is an ethical problem with harming animals, then something has gone wrong.

There were people in the 1700s who said that slavery was bad economics. And there were people who said, “Sure, that may be true, but there is also an ethical component — which if you don’t recognize, then there is something wrong with you.” In any other prior ethical problem, whether we’re talking about the status of women or gay people or anybody else, these same issues apply.

How did you develop the interests that would define the advocacy of your adult life?

My background is entirely different from what I do now. It’s a little odd for me to be advocating a vegetarian diet. My grandfather was a cattle rancher and my uncles and cousins still raise cattle. They’re good people, and I’m still close to them.

A year before I went to medical school, I worked as an assistant in a morgue. One day I had to prepare a cadaver for examination. This was a heart attack victim. I cut in and removed a section of ribs. Then the mortician opened the heart, and the arteries were clogged with fatty deposits. Later, I went upstairs for lunch and in the hospital cafeteria they were serving ribs. The sight of those ribs was so similar to the section of human ribs I had just handled that I just couldn’t eat them. That set me on the path to vegetarianism.

Didn’t you adopt a mouse at some point?

I had a rat. Rats are one of the most unreasonably denigrated species. When I was in college I actually did experiment on rats. The experiments were not just old-fashioned, but downright nasty B.F. Skinner behavioral experiments. It didn’t bother me at the time; I had gone hunting while I was growing up.

You hunted?

I don’t want to give the impression that I was a frequent or especially accurate hunter, but yes, my father occasionally thought it would be a wonderful idea for us to go out and disrupt the stillness of dawn.

Anyway, I ended up bringing a rat home with me. And as long as he was in the cage I didn’t think much about him — I use “him” instead of “it” because animals have gender, unlike a strawberry. But when I let him run around the apartment, I realized that these animals were a lot like dogs or any other social animal. He eventually developed a breast tumor and died a very miserable death. Seeing an animal that no one respects display all the emotions and desperation you would expect to see in that margin between life and death really made an impression on me.

Robert Smith, a Republican senator from New Hampshire, has said: “Concern for animals should not be the exclusive concern of a single political party, just as concern for the environment, human rights and national sovereignty are bipartisan issues.” In your dealings with Congress have you determined whether animal and nutrition issues are perceived as partisan issues?

I think they are entirely bipartisan. And I’m happy that whatever other seismographic changes there might be in the political landscape, I don’t think this new administration will be any less sympathetic to either health concerns or ethical issues in research.

So you have no specific worries about the Bush administration?

Not in this regard. There have been appropriate concerns raised over other aspects of this administration. One party is no better than another. When Bill Clinton was running for reelection he bought up $60 million worth of beef. And the government’s explicit and unabashed reason for this was to support U.S. farmers during a farm crisis. Where do you put $60 million worth of beef? They put it in school lunches, in federal hospitals; they threw it in prison food. This was quite out in the open and nobody ever said that children need another burger. Needless to say, it’s the last thing they need.

What do you make of Huntingdon Life Science’s close brush with bankruptcy, thanks to massive and sustained public protest in England?

I think the sooner Huntingdon Life Science and other labs like them are out of business the better off we all will be. I don’t see them as providing a service. They are getting potentially dangerous products on the market using out-of-date animal testing methods that are a hair’s breadth away from a sham and obviously extremely cruel. Frankly, I suspect you would almost have to be a psychopath to work in a place like that. If you’ve seen the undercover videotapes recovered from Huntingdon and other labs, you’ve seen people quite literally torturing animals. If the job is to take animals, restrain them and force them to inhale or digest toxic substances day after day — the Mother Teresas of the world aren’t going to take that job. And you can imagine who will.

Given the formidable institutions and industries you’re up against, is it hard to be optimistic?

It depends on what we’re talking about. Do I think that every American is going to quit smoking? No, I think that one in four is going to hold on to it for their entire lives. Do I think every American is going to adopt a healthy diet? No, certainly not. But many do. So my goal is to promote this information as vigorously as possible. And luckily everybody makes their dietary decisions one meal at a time.

We are winning ground dramatically. You only have to look at all the new health food products on the shelves to see that. Let’s face it, 10 years ago if you wanted to buy a veggie burger, you would have to find a little store with dusty shelves and someone at the cash register named Sunshine wearing a tie-dyed shirt and listening to folk music. And you wanted to kill yourself.

Nowadays, not only are health food stores huge and ripe with thousands of wonderful products, you can also find these products at regular grocery stores and in restaurants. That doesn’t mean that everyone is going to choose these healthy options, but it does demonstrate that there is a huge demand for them.

We also have celebrities joining us. You may have seen our ads with Ed Asner or Mary Lou Henner or Kevin Eubanks, the musician from “The Tonight Show.” And Keenan Ivory Wayans, he’s a vegan.

And Ted Nugent isn’t as popular as he once was.

Talk about sexual dysfunction. Even the Ted Nugents of the world — I don’t think of them as nonvegetarians, I think of them as pre-vegetarians. And once his rather public and extroverted mating ritual ends I think he’ll be able to play his guitar and also be a little bit more thoughtful about the world around him. I mean it’s embarrassing.

I was struck by a statement Indian cabinet minister Maneka Gandhi made about the treatment of cattle in India and the encroaching “McDonaldization” of the Indian diet. She thoroughly understands your position that cycling grain through animals raised to be eaten is both detrimental to human health and cruel to animals. Why do you think we lack these kinds of advocates in our national government?

I think it’s time to up your Prozac dose! The world is not so bleak as you paint it. There are many people advocating for healthy diets and they are getting results. The Dean Ornishes of the world may have been rare 20 years ago, but they are here today. This is a battle we are winning.

But there are not so many elected officials.

Oh, they’ll come along. Dick Cheney has had his fourth heart attack. Man, I’ll tell you, that is a guy who is so ripe to go vegetarian. As soon as he figures out that Dean Ornish has shown that you can reverse heart disease with a vegetarian diet, exercise and not smoking, he’ll do it.