Before making his own argument, Singer examines and illustrates the flaws in several arguments for and against abortion. He considers the pro-choice argument, which he identifies as liberal, and the pro-life argument, which he identifies as conservative. This may not be the best choice of words as people often associate with one political party or the other, and might be given to prematurely base their ideas accordingly.
Singer looks at the fundamental components of the pro-life argument, “It is wrong to kill an innocent human being, and a fetus is an innocent human being, therefore it is wrong to kill a fetus” (Singer 138). This is the basic foundation for more complex arguments, and Singer agrees that the premises are indeed strong. No rational person can argue that it is ethical to kill an innocent human being; therefore liberals cannot attack the first premise. The second premise is what they choose to attack instead, attempting to argue that at some point or another the fetus cannot be considered “an innocent human being”. Singer dismisses these different ideas surrounding fetal development and the quest to find some point where abortion can be perfectly ethical, birth, viability, quickening, and consciousness. The arguments that liberals offer, Singer considers inadequate to prove abortion as ethically correct.
Where Singer does find a flaw in the conservative argument is in the first premise, that it is wrong to kill an innocent human being. Singer points out that this premise lends “special status” to human life. This goes back to his ideas on racism and speciesism, where a human is no more entitled to life than any other animal. So he argues, that conservatives must choose to label the fetus either a human, or a person. By human Singer simply means, of the species Homo sapiens. In this case, the fetus, or any other human for that matter, deserves no more consideration than any other species of animal. By person Singer means that the fetus is conscious, and one cannot argue that the fetus is “either rational or self-conscious” (Singer 150).
Looking over these arguments Singer goes back to his utilitarian perspective and the consideration of interests. Singer points out that there is a conflict of interests between the mother and the fetus (given the circumstances that the mother does not want to be pregnant). Singer lends greater importance to the interest of the mother, and based on this makes his case in favor of abortion.
Singer considers three different types of euthanasia; voluntary, involuntary, and non-voluntary and the moral issues surrounding each. He identifies voluntary euthanasia as “carried out at the request of the person killed” (Singer 176). With regard to voluntary euthanasia, Singer contends that death is in the best interest for person who is wishing to die. Naturally, if a person wants to live, then it would be unethical to kill that person. But by that same token, if that person is in such suffering that he or she wants to die, then it would be unethical to force them to live. Singer also argues that a law prohibiting voluntary euthanasia would have us living in fear of a slow, miserable death.
As far as involuntary euthanasia, Singer sees no justification in the case where the person does not want to die. He sees the possibility for a situation where the person is in such agony that their "life is so bad bas as to not be worth living" (Singer, 201). What he does not see is the ability for a person to determine that about another person's life.