PETA (People for the Ethical Treatment of Animals) people typically oppose the idea of human exceptionalism: that humans are qualitatively different from, and qualitatively superior to animals.  Such thinking explains their ad campaigns like “Holocaust on a Plate,” in which they compare eating chicken to the extermination of Jews by Hitler.  While PETA people may deny human exceptionalism with their lips—and often with their deeds—I would venture to say that most of them do not truly believe humans and animals are morally equivalent.

I came up with a question you can ask a PETA person that will either help them see that they don’t really believe humans and animals are moral equals, or help you expose their moral confusion for what it is.  Ask him/her, “Do you believe it is ok to sell a dog?”  If they say no, then they really do believe in the moral equivalence of humans and animals.  My guess, however, is that most will say yes.  If they do, proceed to ask them, “Do you believe it is ok to sell people?”  If they say no, then they haven’t completely abandoned the idea of human exclusivism.  In some sense they understand that humans are more valuable than animals.  Of course, they might respond with a second yes, in which case their moral sense is in worse shape than we thought!

The tactic underlying this approach is to appeal to an individual’s moral sense, particularly their understanding of the difference between intrinsic and instrumental value.  That which possesses intrinsic value is to be valued for what it is in itself; that which possesses instrumental (extrinsic) value is valued for what it can provide us (and the value it provides us often leads to something of intrinsic worth).  Humans possess intrinsic value, while animals possess instrumental value.  Humans are to be valued for what they are, not what they can do for us.  They are not a means to an end, but an end in themselves.  That is why they are not to be bought and sold.  Animals, however, are not valued for what they are, but for what they do for us.  That’s why even the strongest of animal rights supporters typically don’t have a problem with the buying and selling of animals, but they do have a problem with the buying and selling of people.