Please read this Wikipedia entry on "Speciesism." Take a particular look at the section about the "Argument from Marginal Cases."

http://en.wikipedia.org/wiki/Speciesism(Links to an external site.)

What do you think about Singer's argument here that if we are to avoid speciesism, we must at least consider doing to human animals what we now do exclusively to non-human animals -- assuming both have similar levels of sentience or the ability to feel pain.

For example, if we are going to experiment on rabbits (for product testing or medical research), then must we also consider experimenting on human beings with similar abilities?

If we argue in response, "But Singer, humans have a special dignity animals do not have," Singer would ask us to think carefully about whether that prejudice ("human chauvinism") towards our own species is morally justified.

He argues that just like valuing the interests of one's own race, gender, or sexual orientation above others is morally wrong, isn't valuing the interests and feelings of human animals over the similar interests and feelings of other animals, merely because we are homo sapiens and regardless of whether we are without brain activity (or even without a brain at all), morally wrong? For Singer, a moral person must look at the particular traits of the animals involved and judge accordingly, instead of automatically assuming that human animals' minor interests ought totrump other animals' major interests.

Why, in other words, would one think it is moral to experiment on a conscious adult rat, dog, cat, or primate, yet never even contemplate experimenting on a human being with a similar, ora decreased,level of ability and sentience?

Singer would ask, "It is complete speciesism to cause suffering to a highly conscious non-human animal, with a social life and the ability to feel pain, yet never contemplate experimenting or using a human being of comparable abilities, for example, someone who is in a permanent vegetative state, who can feel no pain and has no consciousness. Why are fully conscious and awarecats, dogs, and primates experimented upon, yet we (in our speciesistmindset) would never dream of experimenting, for instance,on a childborn without a brain or someone in a permanent coma?"

Does the "Argument from Marginal Cases" work? Please explain.