This is a followup to the running (and persistent) debate over abortion on the Planned Parenthood and Teen Pregnancy thread, and on a few others. I alluded to the question in passing, but I'd like to address it more fully here.
The presumption in the abortion debate is that a human fetus is just as alive and just as human--and therefore as valuable--as an infant, or a child, or an adult.
Let us agree that a fetus is alive. This is self-evident. If it were dead it would not grow. Let us also agree that it is human. It could not be otherwise. Human sperm and human eggs cannot combine to form anything other than a human embryo, which will inevitably become a human infant, unless the process is interrupted by biological, chemical or mechanical means.
So. No arguments so far, correct? A zygote, an embryo, a fetus and an infant are all equivalent in their being alive and human.
Let us for the moment sidestep issues of sentience or viability outside the womb. Let us assume that the living human embryo will, if not hindered from doing so, develop into a healthy baby.
Now, the question. Does this embryo have objective, inteinsic value, by virtue of its being alive and human?
We'll also sidestep the fact that even a dead embryo or fetus has some value to scientific and medical science. Let's confine the conversation to a living human organism. Is it a thing of value, and is its value determined by the fact that it is alive, or the fact that it is human?
How valuable is it, why is it valuable, and who decides?
The answers I've heard range from the tautological ("a human life is valuable because it's a human life") to the legalistic ("a human life is valuable because we all have the right to life") to the religious ("a human life is valuable because we are created by God in his image") to the non-argument ("it just is, and how can you even ask such a question?!")
(Parenthetically, I hear the same arguments about money. Why is a US dollar valuable? It just is. The government tells us it is, and we believe it. But that's another matter.)
I said on the other thread that everyone falls into a continuum of perception of the intrinsic value of life. On one end, we might find a person who believes that all life, from the lowest orders to the highest, is equivalent in value, and it is wrong to end the lives of any living thing, animal or vegetable. Far off on the other end, we have what we might term the sociopath or psychopath, who believes that only his own life is valuable.
In between we have those who think the lives of their family members are more valuable than the lives of others, that the lives of members of their own tribe or nation are more valuable than those of other tribes or nations, and those who believe that the lives of members of their own species are the only lives with any real value.
Understandably, we all fall on different points of the "perceived value of life" continuum, which is why I anticipate getting a range of different answers.
So tell me: is life intrinsically and objectively valuable, does some life have more value than other life, how valuable is life (in concrete terms: words like "priceless" or "precious" are meaningless), and why?