by Chet Raymo
"(You probably read the story last week about the European researchers who produced a lab-grown beef burger from stem cells from a living cow. Which raises again the distinction between natural and artificial. I started to write about this, then remembered that I had already done so back in 2007. I'm repeating that series of posts this week, to remind myself what I thought then, and to learn what you think now.)
Nothing more exacerbates my nature writing colleagues than the mechanical metaphor for life. Think of life as a machine, they say, and you'll treat life as a machine. We will only preserve what we cherish, and no one loves a machine. Life is an organism, irreducible to its component parts. Well, fine. And certainly we have the pleas of Wordsworth and Goethe ringing in our ears: To dissect is to murder.
But the problem arises when we want to understand exactly what life is, where it came from, and how it works, a goal that even the most ardent romantics can aspire to, unless of course they are willing to forego the benefits of modern medicine. So far, the most fruitful- the only?- way of doing biology has been reductionism, pulling the organism apart and inspecting it piece by piece.
These thoughts came to mind as I looked through a recent issue of "Nature." Article after article invoked the mechanical metaphor for life. Protein "motors." Intercellular "sensors." "Scaffolds." And so on. One remarkable article, "Determining the architecture of macromolecular assemblies," is devoted entirely to "a mechanistic understanding of the cell." Take a look at the illustration at below from another article, "The molecular architecture of the nuclear pore complex." It will surely look familiar to anyone who has taken a few machines apart.
A distinction between natural and artificial goes back at least to Aristotle and Plato. It is a distinction that is becoming increasingly irrelevant. Living organisms look more and more like machines, and machines look more and more like living organisms. Is a computer-controlled artificial limb fitted on an Iraq war vet natural or artificial? OK, artificial. What if we find a way to regrow limbs, which is very much within the realm of possibility? Is such a limb natural or artificial?
The natural/artificial distinction is subtly at work in our discussions of religion, conservation, genetic engineering, food production, food consumption, virtual realities, computer intelligence, medicine, contraception, and heaven knows what else- troubling our consciences, complicating analysis. We are deeply ingrained with the notion that "natural" is good, and "artificial" is- well, artificial, as in "She has an artificial smile." Even the secondary meanings of the words have moral implications. This is a deep and perplexing subject.
The thing we know best is our self. We experience our own agency and will and "naturally" tend to ascribe agency and will to other people, animals, even inanimate objects. Our ancestors invested rocks, mountains, streams, clouds, and celestial objects with the attributes of life. Animism was the first philosophy.
A corollary of animism is artificialism: Whatever exists is the product of conscious design. The thunderbolt and the earthquake happen because someone makes them happen. Zeus hurling from on high, for example. Artifacts require artificers, Thus the spirit world, gods, God. Piaget and others have shown that animism and artificialism are the default explanations of children, undoubtedly for the same reason they were the default explanations of humankind.
Beginning with the pre-Socratics, certain philosophers entertained another idea. Things happen not because of agency and will, but because they are constrained to happen by "natural laws." The search for these laws began with astronomy, and has been gradually extended to almost every area of human experience. As more and more phenomena were seen to act in accord with "the laws of nature," the spirit world was rendered largely superfluous. The naiads and dryads, the fairies, the mountain trolls, the angelic choirs who pushed the planets in their courses- all sent packing. Artificialism gave way to naturalism.
Have all phenomena been reduced to natural law? Of course not. Consciousness, the origin of life, the origin of the universe, the origin of the laws themselves continue to resist our probing, although remarkable progress has been made. Where natural explanations are not yet available, the naturalist will say "I don't know, let's continue probing." The artificialist will claim an artifact and presume an artificer. So-called intelligent design is the latest pseudoscientific manifestation of artificialism.
"I don't know" and "God did it" have exactly the same explanatory content: Zero. Yet the great majority of us continue to posit an artificer, and waste a huge amount of human energy championing one idea of the artificer over another.
Why not just let the distinction go? Instead of natural and artificial, how about known and unknown, or law and mystery. Look again at the diagram I posted yesterday. Even without understanding the biochemistry, how can anyone look at this diagram and not be struck dumb with awe, reverence, celebration, praise? The more we learn about the way the world works, the more we become aware of our ignorance. We are made no less ignorant by endowing our ignorance with personhood, agency and will. Natural/artificial is one more outmoded duality-like matter/spirit, body/soul, nature/supernature- that explains nothing and makes life on a crowded planet fraught with disagreement."