Tuesday, April 7, 2020

The Origin of Life

Yesterday we took a brief look at a new book by physicist Paul Davies titled, The Demon in the Machine: How Hidden Webs of Information Are Solving the Mystery of Life. I observed in that post that Davies, an agnostic, occasionally walks right up to the brink of acknowledging that life must be the product of an intelligent designer but at the last moment veers away from drawing that conclusion.

Toward the end of this fascinating read he not only walks up to the line, he actually sticks his toe over it. Here's how:

On page 172 Davies replies to the question posed in the title of this post by exclaiming that, "The short answer is, nobody knows how life began!" He goes on to explain that nobody even has a plausible theory for how the enormous difficulties involved in generating even the simplest living cell could have been surmounted by natural processes. 

 He writes that, "An explanation for the origin of life as we know it has to include an explanation for the origin of...digital information management and - especially - the origin of the [genetic] code," as well as the entire translation system necessary for converting the information inscribed in DNA into proteins. The translation system is comprised of numerous kinds of proteins, but where did they come from before there was a DNA to code for them and a translation system to produce them and the information to choreograph the whole process?

In other words, this complex system had to pretty much exist in order to bring itself into existence. Davies states that this is the most formidable and perplexing problem in all of evolutionary biology.

Moreover, each step in the evolution of a living cell must somehow be conserved in a kind of ratchet effect which allows for its preservation before the next step occurs. What constituted the ratchet and where did it come from?

So many are the conditions that need to be satisfied to produce life that Davies and many other scientists are beginning to think that it may have arisen only once in the entire history of the universe. Contrary to what we often read in the popular media, the discovery by astronomers of an earth-sized planet in the habitable zone of some star is scarcely reason, by itself, to assume that life could exist there.

Davies voices his skepticism of the enthusiastic claims that often surround these discoveries:
Suppose the transition from non-life to life involved a sequence of a hundred chemical reactions, each requiring a particular temperature range (for example, 5-10°C, for the first, 20-30°C, for the second, and so on). Perhaps the transition also demanded tightly constrained pressure, salinity and acidity ranges, not to mention a host of catalysts....habitability does not imply inhabited.
And these conditions are just a few of the requirements that must be met for a planet, even one with water on its surface, to give rise to living things.

Even if some day a researcher manages in a laboratory to synthesize a living organism from a residue of raw chemicals it would demonstrate only that life can be created by an intelligent researcher who can establish all the necessary, tightly controlled conditions in her laboratory. It would prove nothing about what could actually happen in nature in the absence of an intelligent scientist.

Davies again:
To attain even the modest successes [creating life in the lab] announced so far requires special equipment and technicians, purified and refined substances, high fidelity control over physical conditions - and a big budget. But above all it needs an intelligent designer (aka a clever scientist).
And that clever scientist must have a purpose or goal in mind toward which he is striving, but, he writes, "Astrobiologists want to know how life began without fancy equipment, purification procedures, environment-stabilizing systems and - most of all - without an intelligent designer." (p.179) (emphasis mine).  

As Davies goes on to say, just because an intelligent agent can easily manufacture an artifact doesn't mean that nature could do it even given a billion or more years: "...organic chemists can readily make plastics, but we don't find them occurring naturally. 

Even something as simple as a bow and arrow is straightforward for a child to make but would never be created by an inanimate process." Indeed, but nevertheless many scientists have faith, a blind faith, that the unimaginably complex and purposive processes in the cell, plus both the material hardware and the informational software, have been created by just such an inanimate process.

And why do they believe that with such conviction? Not because there's evidence for it, but because they're committed to a naturalistic worldview, or at least a naturalistic methodology, that excludes apriori the possibility of the existence of an intelligent designer. If the possibility of a designer is automatically ruled out then some naturalistic theory, no matter how implausible, must be true.