To learn about the value of something, you must, in a sense, see the value of it. You cannot simply be told that it is valuable. Currently, the value of life is debated. Now, it is possible that someone may learn that life is valuable because of these debates, but they will not come to know life as valuable through reason alone. To know life as valuable, life must be seen as valuable--life's value must be seen. There is no place for arguing about the value of life, anymore than there is a place for arguing about the value of a car. Show me that the car runs, then I may see its value. If we disagree about values, then we disagree about where to look for values. Now, show me why an unborn life has little to no value? Where are you looking for their value?
If life has no purpose apart from the purpose that person gives it, then we cannot argue that any life has value before the one living it gives it value. Since Sartre, at least, people have claimed that our lives only have purpose insofar as we give our own lives purpose. But there is more, even in Sartre, than that. Sartre said that we, by our actions, choose a purpose for all lives. In Sartre's view, if I do something, I am claiming that what I did was a good action for anyone. By my living, then, I claim that everyone ought to live. Is it situational? Maybe, but what situation are you pointing to? Is life so worthless that you do not fight for it? I do not care what one thinks about whether people have souls, what I care about is whether they will be like you in any way. Do you think that because they will never be able to understand what you can, that they are less human? Or is it because they cannot do what you can? Well, then, may the PhD.s and marines, etc., live, and all others--incompetent as they are--be put to death. Do you think this is a strawman? It is not, it is simply shifting perspectives and shrinking the gap. You can argue that ordinary people can do things that PhD.s and soldiers can't, but then, are you sure I can't use that against the original argument?
Besides, are people valuable because of what they do, or because of what they show? The most incompetent person can show the worth of living, simply by their valuing their own life. If life is valuable because of what people do or understand, then people have most value in the prime of life, but we don't act like it. In December we showed that we do not value people by what they do or understand. We mourned when children died. Do you find value in possibility, in potential? But if we do not have value except as we make it, then we do not have value except as we make it, and we cannot make potential. You cannot know what a person might have achieved. You cannot assess a single person's value by their potential, only by what they have achieved. Maybe you use statistics? "only 0.1% of people born like this ever achieved anything." What an absurd statistic! How do measure whether someone achieved anything? What must they do? Invent something? Go to the moon? Become president? But children and idiots can change people's lives. If they are capable of life at all, then they can love people, and that can change people.
Where do you look for value? If value is found in fulfilling a purpose, then who are you to decide another's purpose cannot be fulfilled? If they do not fulfill a purpose, it is their own fault, according to Sartre. Either, at birth, a person's purpose is nonexistent, in which case why should any of us live? We all have the same claim to life at that point. Or, again at birth, a person's purpose is indeterminate, in which case how do you know their purpose won't be as simple as "to live"? There is a third option, that there purpose is determined, "to glorify God," but, in a materialist world, that cannot be allowed, and besides, it still doesn't give any reason to stop a life from existing.
When one is counted as alive does not matter. That one will be counted alive, if nothing gets in the way, is enough to count one as alive.
This all was triggered by this: http://thegospelcoalition.org/blogs/kevindeyoung/2013/04/11/the-story-you-may-not-have-heard-warning-graphic-reading/ but I should note that my tiredness of certain arguments against abortion (that the soul originates at conception, that it is murder, that it is an offense to the image of God in them, etc.), which ignore where the actual differences are, contributed to my actually writing it. The problem is that we don't agree about where to look for a person's value. From this arises disagreements about the value of fetuses, confusion about the value of various different kinds of people, confusion about what I am saying about your value when I say you did, or are doing, something wrong.
The love of God: independent of what we do or understand, but only
dependent on his mercy in Christ Jesus our Lord, granting us to know his
love and to depend on his grace to enable us to live in him. Our value
is Christ, and if we cannot claim independent worth, then why should we
look for some in others? Rather we look on them as justified--either, as
we would rather, in Christ or by themselves suffering the justice of
eternal punishment for sins in hell, thus having their guilt removed
from them (once the eternal punishment is done)--this is to live in
light of eternity: to accept that their sins will be removed by God, not
by us, even if it is never completed, as is the case if they suffer the
eternal punishment by themselves. Therefore, because it is God who
justifies, we can love all others with his love. They are not now just,
and will never be finally just apart from Christ, but one day they will
receive what they deserve--either due to their own sins or Christ's
perfection--and we therefore have no right to condemn them now. So, this http://thegospelcoalition.org/blogs/tullian/2013/04/12/confessions-of-a-performancist/ is how we view value, and that makes a huge difference in where we look for the value of people, and that is why we care about the people who are, really like us, incompetent, deformed, idiots, poor, and helpless.