You: But that process is essentially the same one by which humans reproduce. Genetic material in the mother's womb creates copies of itself in increasingly complicated ways, eventually ending up as a child. Are you saying that a fetus is not alive because it is the result of a chemical process?

Aaron: Don't be ridiculous. A fetus is alive because God places a human soul into it at the moment of conception.

You: So what you are saying is that a living thing can be formed out of inanimate matter just so long as God takes a hand in it.

Aaron: Finally we are getting somewhere! That is precisely what I am saying. So now do you see the necessity of God's existence?

You: Not at all. All you have shown me is that there is a smooth transition between inanimate matter and a fetus and that you cannot say when the thing stops being inanimate and starts being alive without invoking the concept of God. It seems to me that you are just using God as a handy shorthand for the moment of "becoming alive".

Aaron: Don't be ridiculous! God is more than a matter of convenience!

You: But you're using him as one. For instance, if I picked up a stick and whittled it into a toothpick, you wouldn't say that, at some point, God had put the spirit of a toothpick into the stick, would you?

Aaron: Of course not! But that's an entirely...

You: It's exactly the same thing. You couldn't point to a moment when the stick becomes a toothpick any more than you can point to the moment that a set of genes becomes a child so you invoke God.

Aaron: But I can point to a moment, the moment of conception! That is when God puts the soul into the child.

You: How do you know that? Perhaps that's just the moment that the mechanical process of baby-making begins and God puts the soul in on the first Sunday after the first full moon after conception?

Aaron: Ridiculous! How dare you...

You: Oh, that's right. I forgot that God doesn't work Sundays.