Part 1 is here. Please see part 1 for the intro to this series.
Reason #2: Nobody knows when life begins. [related - When life begins is a matter of opinion/religion/etc.]
This is really several related reasons, because the statement is ambiguous. Do they mean life as in any kind of life, or ensoulment, or some other definition of "human" that they have decided to use as a basis. No matter what they mean, the premise is false, and I'll get into that later.
But lets assume for the sake of argument that it is true. We know a human life emerges from the womb, and we know the process starts at conception. So at some point no earlier than conception and no later than birth, a human life begins. Let's say that nobody know when this happens. It could be at any point during the pregnancy. Nobody knows.
Based on that premise alone we should stop all abortions immediately! Why? Because we wouldn't know if we were killing a human being. Let's say you are driving down a residential street and purposely run over a box in the street. "I didn't know if it was a person" is not a valid excuse if there were a child playing inside it. You should have avoided the box altogether in case there was a child there. Or take the example of a hunter in the woods. He sees something moving in the bushes. It might be the deer he's after, or it might be another hunter. By law and reason he must assume it could be a hunter and not shoot until he is sure that it isn't.
So the entire argument is based on faulty logic. If you don't know when life begins you must not abort! Using that argument to support a pro-choice position is fatally flawed.
Of course we do know when life begins, thanks to modern medical science. It is not a matter of religion, or opinion, or guessing. It is a proven, uncontested scientific fact. It begins at conception, when the egg is fertilized by the sperm. At that point a new organism is formed that is genetically unique. That organism is alive from the beginning. According to Wikipedia (sorry folks, but it does not differ substantially from textbooks), something is alive if it exhibits the following characteristics (I have shortened the entry in the interests of brevity:
An embryo exhibits these characteristics from fertilization onward.
- Homeostasis: Regulation of the internal environment to maintain a constant state.
- Organization: Being structurally composed of one or more cells, which are the basic units of life.
- Metabolism: Transformation of energy by converting chemicals and energy into cellular components (anabolism) and decomposing organic matter (catabolism).
- Growth: Maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter.
- Adaptation: The ability to change over a period of time in response to the environment.
- Response to stimuli: A response can take many forms, from the contraction of a unicellular organism to external chemicals, to complex reactions involving all the senses of multicellular organisms.
But perhaps the person doesn't mean just life, but human life. Again, science to the rescue. The law of biogenesis states that organisms reproduce after their own kind. That is, pandas have baby pandas, whales have baby whales, cats have baby cats, and humans, surprise, have baby humans. To say that a fetus isn't human begs the question "to what species does it belong?"
To quote some doctors/scientists on the start of human life:
Dr. Jerome LeJeune, professor of genetics at the University of Descartes in Paris, was the discoverer of the chromosome pattern of Down syndrome. Dr. LeJeune testified to the Judiciary Subcommittee, “after fertilization has taken place a new human being has come into being.” He stated that this “is no longer a matter of taste or opinion,” and “not a metaphysical contention, it is plain experimental evidence.” He added, “Each individual has a very neat beginning, at conception.”Occasionally you will hear "religious" or "spiritual" people define the question in terms of ensoulment. "we don't know when the fetus gets a soul". Of course that is still subject to my initial argument - if you don't know you must not abort. However, I think we can do better at dismantling this argument. The usual suspect brought out is Thomas Aquinas. According to Cardinal O'Connor:
Professor Hymie Gordon, Mayo Clinic: “By all the criteria of modern molecular biology, life is present from the moment of conception.”
Professor Micheline Matthews-Roth, Harvard University Medical School: “It is incorrect to say that biological data cannot be decisive.... It is scientifically correct to say that an individual human life begins at conception.... Our laws, one function of which is to help preserve the lives of our people, should be based on accurate scientific data.”
Dr. Watson A. Bowes, University of Colorado Medical School: “The beginning of a single human life is from a biological point of view a simple and straightforward matter—the beginning is conception. This straightforward biological fact should not be distorted to serve sociological, political, or economic goals.”
A prominent physician points out that at these Senate hearings, “Pro-abortionists, though invited to do so, failed to produce even a single expert witness who would specifically testify that life begins at any point other than conception or implantation. Only one witness said no one can tell when life begins.”
Although some people point out that Saint Thomas Aquinas thought the soul did not come to the fetus ("ensoulment") until sometime after conception, the fact is that he considered abortion gravely sinful even before this time. He taught that it was a "grave sin against the natural law" to kill the fetus at any stage, and a graver sin of homicide to do so after ensoulment.So even though Aquinas thought that the soul was created after fertilization, he didn't consider that the "unsouled" embryo was not worthy of protection. But we can go Aquinas one better because we have science on our side today. As Christians (and in most other religions that ave a concept like "soul") we believe that the soul is the essence of something that makes it alive. In other words, every living thing has a soul, although not all souls are human souls. Since we now know that the embryo is a new living organism at the time of conception, by definition it is "ensouled".
Again, perhaps the person means a human soul, to which I ask "at what point do you think God removes the original soul and replaces it with a human one?" The only position that does not lead to an absurd conclusion is what the Catholic church teaches - that a human soul is present from the moment a human life begins, and that moment is the point of conception. If you don't believe in souls altogether, that is your right, in which case you can accept the scientific and logical arguments above.
To be fair, I've been throwing around the word "conception" a lot. Some will claim that we don't know when life begins because "conception" is not an exact point in time - the process of fertilization takes a finite amount of time, and is not instantaneous. I will grant that it is not instantaneous, but we are still talking about the course of the first few minutes of a pregnancy, not days or week, at which time abortions are performed. Even the "morning after" pill is killing an existing human being. Such an argument is only trying to muddy waters, and has no impact on the conclusion.
So the next time someone says "nobody knows when life begins" thank them for arguing a pro-life position for you.