2nd argument: Life Cycle
A 3 month- old fetus is not the same as a fully matured baby. We in our society have a standard of life, a plant is not worth as much as an ant is not worth as much as a dog, a dog as a human etc. Therefore, a fetus is not of the same value as a human baby based on this measure of life. The difference is, the fetus can become a human, so it will change from one 'value' to another. Does this give it greater life value?
OK. This goes back to a point mentioned earlier. It’s a matter of demonstrable, objective, scientific reality that the foetus conceived by a man and a woman is human – in the strictly biological sense of “human”
. That is, it has human DNA. It is made up of human cells. It belongs to the species homo sapiens
. Etc, etc.
But the point that you make here is that there can be other senses of “human”. For example, we often make a distinction between humans and animals. Strictly speaking, this is not correct; humans are
animals. And yet it’s a meaningful use of the word “human”; it calls attention to the characteristics of humanity which are unique to humanity, and not shared by other animals.
Consider the concept of “human rights”, which is obviously relevant to the issue of abortion. Your right to, say, freedom of conscience, or freedom of expression, or freedom of assembly necessarily entails my obligation to respect that right. And why, fundamentally, am I obliged to respect your right to conscience, expression, etc? Is it because we share the same DNA? How does that follow? No, a more credible account is that you have a right to conscience, etc, because you have capacities that are not shared by other living beings – dogs, earthworms, cabbages, athlete’s foot fungus, the influenza virus. You have capacities for reflection, for communication, for imagination, for empathy, for emotion, for abstract thinking, for creativity, for forming relationships which distinguish you from species which have these capacities only in a limited form or not at all. These capacities claim our respect; this is what makes you “human” in the philosophical sense of a person whose rights command our respect.
But this requires careful thought. If the capacities for reflection, for forming relationships, etc are what constitutes humanity in this sense, are the profoundly disabled correspondingly less human according to the degree of their disability? Go too far down that
road, and the cries of “Nazi!” start to become justified. And yet, in many respects, the (unhandicapped) foetus is closer to those capacities that the profoundly disabled are, since the foetus is actively developing all of these capacities, while a profoundly disabled person is not, cannot and never will.
The second problem with this view of the matter is that we lack most or all of these capacities for quite a long period after
birth; the newborn infant is a wriggling bundle of instincts. If our humanity depends on us actually having developed these capacities, then we are all subhuman for at least the early months of our lives. In fact, we don’t fully develop all of these capacities until well into adolescence. (And, arguably, some of us descend into subhumanity again at the end of our lives.)
In short, if the lack of these capacities justifies abortion, it seems also to justify infanticide and the destruction of the bewildered and demented. That’s not a conclusion we can be very comfortable with, but it’s hard to avoid it.
It seems to me, then, that, important as these capacities are, the fact that we are ordered towards these capacities, that we are developing them, that they are characteristic of our natures, is of more moral significance than the fact that we actually have them fully developed at a particular point in time. Which means, I think, that this is not a helpful avenue to explore when seeking a moral justification for abortion.