A number of proponents of “Intelligent Design” attempt to show, possibly using the Drake equation, that the occurrence of intelligent life anywhere is extremely unlikely, that a miracle would have been required to create us, to explain our existence.
I can’t help but think this backwards. Doesn’t this argument show that we were not part of the design but something added afterwards?
Let’s approach the problem from a different direction. What is the mark of intelligence? What is the clearest evidence of its presence? Language. If in future times we explore other stars and chance upon a book we will know with certainty that an intelligent race produced it.
But there is more than one kind of language. We develop languages for different purposes: speaking, writing, and even communicating with our machines. This last type of language is called a programming language, and at its fundamental level it is a linear sequence of binary data.
Now consider DNA. It is a programming language for life. It is base 4, not base 2 like our programming languages, but this difference is trivial. (although the density of genetic material is also important) The fact that it comes in strands makes it even more similar to a book or a linear seqence of program instructions.
Where does DNA come from? While we don’t yet know exactly how it is created, simulations of planetary atmospheres suggest that nucleic acids can be formed there by fairly natural processes. Can these components, and strands of DNA or RNA themselves, can come about on their own as a consequence of the laws of physics themselves? Let us assume that this is so.
If language signifies intelligence, and DNA is a language written in the very physical laws of the universe, then we argue that there is a primeval intelligence who is the author of those laws: God. I would say that DNA and evolution should form the backbone of the Christian argument for design.
If this reasoning is correct, life should be relatively common in the universe. Perhaps discoveries like the habitable world Gilese 581c are our first steps to verifying this hope. Of course, we should not be too narrow minded in our consideration of what a habitable world is, as some bacteria can live without water and little oxygen in a tar pit, and some grow faster in the presense of ionizing radiation.