Trying to rationalize abortion using this argument is utter nonsense.  If we don’t know when life begins, then we can’t say it has begun at birth, or at age five, or at 50.  By this logic, the law could never convict someone for murdering a 30-year-old woman because there is no way to prove that she was alive. 

The fact is, no scientific, biological, or medical textbook says that life begins at any point other than conception.  Further, simple deductive reasoning proves that life begins at conception because that is the only time it can begin.  Any other point is strictly arbitrary.

However, even if it were true that no one can prove when life begins, that is not a justification for legalized abortion. 

The pro-life position is that the unborn should be left alone.  Obviously, a person does not have to prove anything about the unborn in order to justify taking that view.  On the other hand, the pro-choice position is that it should be legal to butcher the unborn by the millions because no one can prove that they are living human beings.  To appreciate just how irrational this is, imagine that the judge and jury in a capital murder case sentenced a man to death because no one could prove that he was not guilty.  The public would be justifiably enraged.  They understand that the state is the one taking action and that, therefore, the burden of proof belongs to them.  The prosecution is required to prove that the man is guilty in order to convict him, but the defense has no obligation to prove anything in order to justify leaving him alone. 

In other words, our judicial system is designed to err on the side of life.  We would rather let a thousand murderers go free, than execute even one innocent person. 

The question is why we don’t apply this standard to the unborn.  Why aren’t we saying to the pro-choice mob, “Before we’ll let you kill the unborn, you have to prove that they are not living human beings.”  After all, to say that no one knows when life begins is, at the very least, an acknowledgement that it might begin at conception.  Shouldn’t we leave the unborn alone until we find out for sure?  Saying we can execute the unborn because no one can prove when life begins, is no different than  saying we can execute an accused murderer because no one can prove he’s innocent.

Amazingly, when cornered on this, some abortion apologists will contend that abortion should be allowed even if we accept that the unborn are living human beings.  The question then becomes, if the humanity of the unborn is irrelevant when deciding whether they can be killed, why is the humanity of a five-year-old relevant when making the same decision?

As for this brainless contention that women must be allowed to decide when the lives of their children have begun, imagine two children who are conceived at the same moment.  Three months later, one mother talks about her baby, knows its sex, has named it, and has even seen it on an ultrasound screen.  The other mother believes that the life of her child hasn’t begun yet and decides to have it killed by abortion.  The pro-choice mentality is that both mothers are right, despite the fact it is physically impossible for that to be true. 

Also, if women are to be the ones who decide when life begins, why should they lose that right by giving birth?  If a woman who sincerely believes that life doesn’t begin until speech is possible, kills her three-month-old daughter, should she be charged with murder?  What makes her belief that life begins at speech less valid than another woman’s belief that life begins in the second trimester, or at birth, or at any other arbitrarily chosen point?  And what gives society the right to charge this woman with murder, while saying that women are the ones who decide when life begins?