Sunday, April 22, 2007

The importance of hooks and tendrils

Take the train from London's Victoria Station to the town of Orpington, fifteen miles south of the city. Here you might catch a bus or a taxi for the last leg of your journey, but I chose to set out on foot across the English countryside, along leafy lanes, across grassy meadows. My goal: the picturebook village of Downe, and, nearby, Down House, Charles Darwin's home for forty years. Here Charles and his wife Emma raised a big happy family, and here Charles wrote the book that exploded on Victorian culture like a bombshell: On the Origin of Species by Means of Natural Selection.

The house is today in the care of English Heritage and has been lovingly restored to what it was like when the great man and his family were in residence. His study is as it was when Darwin sat in his chair penning the 155,000 words that would revolutionize our understanding of our place in nature; every horizontal surface is covered with the tools and collections of a curious mind -- fossils, flints, plant specimens, books, microscope. The greenhouse at the back of the house is stuffed with plants, as it was in Darwin's day. At the back of the property is the "Sand Walk," where Charles would go to walk and ponder the significance of his exhaustive -- and exhausting -- observations.

He was not a well man. He suffered terribly from debilitating symptoms that may or may not have been mostly psychosomatic. He sent his great book off into the world, and, as all of England debated its import, he carried on with his latest research on creeping plants, trying to figure out how they evolved. His biographers Adrian Desmond and James Moore write: "Tables and sills were an entangled mass of twiners and tendrils; pots perched on every ledge as he timed sweeps and tested the effects of light. Warm summer days were spent in the hop fields watching the plants snake up their poles. He brought hops inside, and sat ill in bed tying weights to their tips in an attempt to slow their ascent. Around the house the vines took on a surreal appearance, covered in paint markers as he timed their twisting movements."

On my visit to Down House I sat for a long time in the sunny back garden and imagined Charles across the way in the greenhouse, in his black hat and cape, crouched over pots of twiners, measuring and recording every twist and turn of the myriad tendrils fingering upwards. Were the stem-twiners and the tendril-wavers related, and if so how? Were the grasping hooks of the climbers modified leaf stems? How did the twisting and hooking aid the plants in the struggle for existence? Meanwhile, sixteen miles to the north, churches, newspaper offices, scientific societies, classrooms and drawing rooms were in an uproar of contention and indignation: If all living things were related by common descent from a primeval ancestor, what made humankind unique? If chance and struggle shaped the tree of life, what was the role of Divine Providence? Oblivious to the turmoil, Darwin tended his creepers and twiners.

For most of Darwin's contemporaries, the twining plants were no more of a mystery than any other feature of the natural world. Everything was the work of a supernatural Creator during the six biblical days of creation. A single explanation sufficed. God did it.

God did it was not satisfactory for Darwin. For him the twining plants -- like his ducks and geese and the flinty rocks in his meadow -- were clues to an inexorable script of creation. To say God did it explained nothing; it was merely a concise way to cover our ignorance. What Darwin sought instead was a story of the past that invoked no agency except those that we see at work in the world today, one grand story that embraced the hills, the valleys, the fossil organisms with their similarities and differences -- and, of course, the twining plants and ducks and geese. Every element of the visible world was a clue to the hidden past.

Charles Darwin was not adverse to confessing his ignorance, and did so frequently in his many letters to family and friends. He was especially ready to admit his innocence with regard to the big questions, the questions traditionally addressed by religion: Why is there something rather than nothing? Why are the laws of nature what they are? Who am I? Where did I come from? What does it all mean? Darwin was deeply conscious of the mystery of existence, and reluctant to cover his ignorance with myth and fables. In a letter to the American biologist Asa Gray, Darwin wrote: "I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe what he can." The physicist Heinz Pagels might have been describing Darwin when he wrote: "The capacity to tolerate complexity and welcome contradiction, not the need for simplicity and certainty, is the attribute of an explorer. Centuries ago, when some people suspended their search for absolute truth and began instead to ask how things worked, modern science was born. Curiously, it was by abandoning the search for absolute truth that science began to make progress, opening the material universe to human exploration."

Darwin counted himself an agnostic, but in his reverence for the creative agency of nature we should count him a devoutly religious man. "There is a grandeur in this view of life," he famously wrote on the last page of The Origin of Species. The grandeur of which he spoke of has more of the divine about it than did the anthropomorphic idol who occupied the thoughts of his contemporaries.

(Footnote: The last part of this Musing is recycled from an earlier source. I'm working on a book-length project and hope you will not mind a bit of repetition here.)

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