What if Life Exists on Other Planets?

Suppose scientists discovered intelligent life on a planet in a distant solar system, or perhaps on several such planets. What would be the implications of such a discovery for the validity of one's belief either that God, or a being very much like God, exists or one's belief that no such being exists?

For a long time metaphysical naturalists - those who believe that nature is all there is, there's no supernature - believed that the discovery of intelligent life on other planets would suggest that such life could and would arise anywhere the conditions for it are right and that the existence of living things on earth is thus not extraordinary. It would, in other words, seriously weaken the argument that the origin of life, especially intelligent life, is so improbable that it must be the product of a divine intelligence.

Physicist Paul Davies, an agnostic, believed this himself until he set out to write a book on the origin of life (The 5th Miracle). In the book Davies lists three possible explanations for life's origin, what biologists call abiogenesis (the origin of life from non-living matter).

The biggest problem for which any explanation has to account is the origin of complex, specified information such as we find in the DNA/RNA molecular architecture that forms the genetic code. According to Davies there are three possibilities: Either physical laws generate this specified complexity, or there are unknown biological laws that make it inevitable, or it was a genuine miracle.

Davies invokes science as justification for not considering the miraculous, but he also rejects the first possibility. He writes:

The heart of my objection is this: The laws of physics that operate between atoms and molecules are, almost by definition, simple and general. We would not expect them alone to lead inexorably to something both highly complex and highly specific....A law of nature...will not create biological information, or, indeed, any information at all. Ordinary laws....can shuffle information, but they can't create it.

This leaves him with the possibility of a kind of biological determinism which results from a heretofore undiscovered complexity law or information law that drives matter toward the goal of producing life:

Whereas the laws of physics merely shuffle information around, a complexity law might actually create information....I believe it is only under the action of an informational law that the information channel, or software control, associated with the genetic code could have come into existence.

From the standpoint of naturalism, however, such a law has at least two unacceptable implications. The first is that it flies in the face of Darwinian orthodoxy which claims that naturalistic processes are meaningless, purposeless and directionless. A law of information that exhibits foresight, purpose, meaning and direction and that pushes atoms and molecules toward the goal of increasing complexity would be the undoing of this claim.

The second is that if there is such a law and if the universe is actually suffused with purpose, meaning and foresight that would be compelling evidence for the existence of a super-natural mind, an intelligent architect of the cosmos.

If, though, scientists one day discover that life really is abundant in the universe then that would mean that the existence of such an information law and thus the existence of an intelligent supernatural agent are very likely. In fact, there's no significant difference between life resulting from a kind of biological determinism established by God and a supernatural miracle of instantaneous creation. They're both miraculous. The only real difference is the matter of how long the process took.

In the beginning of the last chapter Davies quotes one of the greatest physicists of the 20th century, Freeman Dyson, who wrote in 1979 that, "The more I study the universe and the details of its architecture, the more evidence I find that the universe in some sense must have known we were coming." The evidence to which Dyson refers has multiplied in the four decades since 1979 many times over.

Davies concludes his last chapter with this:

The search for life elsewhere [in the universe] is thus the testing ground for two diametrically opposed worldviews. On one side is orthodox science, with its nihilistic philosophy of the pointless universe, of impersonal laws oblivious of ends, a cosmos in which life and mind, science and art, hope and fear are but fluky incidental embellishments on a tapestry of irreversible cosmic corruption....

There is an alternative view, undeniably romantic but perhaps true nonetheless, the vision of a self-organizing and self-complexifying universe, governed by ingenious laws that encourage matter to evolve toward life and consciousness. A universe in which the emergence of thinking beings is a fundamental and integral part of the overall scheme of things. A universe in which we are not alone.

What Davies leaves to the reader to ask is where would such laws, laws that direct mindless matter to create consciousness, come from? Of the three possible explanations for the origin of life - physical law, biological determinism and miracle - the first is a non-starter and the other two both lead to the conclusion that there's an intelligence at work behind the universe.

Naturalists can't be happy with this state of affairs.