Philosopher Peter Singer is known throughout the world for his controversial belief that all life is not equally precious. In fact, Singer tells correspondent Dan Rather that it may be ethical to kill handicapped babies and argues that the lives of animals are not inferior to the lives of humans. Rather's report on Princeton University's controversial ethicist will be broadcast on 60 MINUTES II, Wednesday, Feb. 20 (8:00-9:00 PM, ET/PT) on the CBS Television Network.

Although many consider Singer's views on medical research immoral, he maintains that his views are simply unconventional and explains to Rather why he thinks it's better to conduct dangerous experiments on certain humans as opposed to animals. "...I think there, perhaps, are some things which could be done with people who are no longer conscious at all and will never recover consciousness," says Singer. "It would be ethically justifiable to approach the relatives and to say, 'Look, we want to find out whether certain drugs produce adverse reactions in human beings. Do you have any objections to doing this test on your relative who can no longer suffer from it because he or she can no longer feel anything at all?'...Without consciousness, human life has dropped to a level, in fact, below that of a chimpanzee or a dog."

Singer's ethical views about ending life aren't just words scribbled on a college blackboard -- they have real world application. In fact, Singer supported Diane Arnder's court battle against an advocacy group for the right to end the life of her 29-year-old daughter who was suffering from cerebral palsy, severe mental retardation and seizures. "People have to understand you can only do so much to keep a person here and then, after that, it's time for God to intervene...or somebody to intervene and say, 'Hey, it's time to let go,'" says Arnder.

But Steve Drake, a spokesman for Not Dead Yet, the disabled person's advocacy group that asked a judge to intervene in Arnder's case, still disagrees -- he himself survived a childhood brain disorder. "It is dressed up nicely, it is spoken in very polite tones by a very polite person, but what [Singer] is really saying is that some people's lives are not worth living -- are not worth it for us, as a society, to put up with -- is not worth families having kids with disabilities," says Drake.

Jeff Fager is the executive producer of 60 MINUTES II and Steve Glauber is the producer.