Singer suggests that in feeling pain, a human is cognitive and able to respond to this pain. Should a human fetus become able to sense pain, it is then a creature that should not, according to Singer, morally be subjected to mistreatment, physical or otherwise, by others of it's species. As such, it's easy to argue that abortions past that point should not be allowed to take place, as the fetus is now conscious of the fact that it is being hurt. However, in some other cases, such as the example that Singer gives that the fetus will be born with a significant deficit in mental capacity, the fetus may be able to feel pain but is unable to grow to a 'regular' human level. Because of this, and because some humans can believe that human lives do