J. W. Wartick offers “The Epistemic Argument Against Abortion” in which he shows that any reasonable doubt about the humanity of unborn serves only to condemn abortion. He directs his posts to those people who defend abortion with a claim of ignorance such as “We don’t know when human life begins”. He offers this analogy:
Suppose you are a demolition expert. You’re sitting outside a building you are to blow and you are about to hit the button. The area has been declared clear and so you have flipped the cover of the button up and you’re about to blow the building. Suddenly, someone cries out–a little red tricycle has been discovered outside the building. Fortunately, however, the people who spotted the tricycle tell you there is only a 20% chance that the child made his or her way inside the building. The equipment being used is expensive and your company is paying more Shrugging while thinking “Time is money,” you go ahead and press the button, blowing up the building. After all, you’re 80% sure there is no one inside.
Wait a second. That’s horrible!
Unless you know with certainty that the building is empty, you can’t blow up the building. Unless a hunter is sure that what’s moving in the bushes isn’t another hunter, he can’t shoot. This means that pro-aborts must prove their case conclusively (which they can't do).
Mr. Wartick’s post and the comments are certainly worth reading.
