Sunday, November 15, 2009

Reading Journal: The Science of Leonardo

I was hoping this book (by Fritjof Capra who wrote The Tao of Physics) would describe a more humane form of science, one that does not forget richness and complexity as it travels down its reductive rabbit holes. Which seems to be what Capra is promising in the beginning: "What we need today is exactly the kind of thinking and science Leonardo da Vinci anticipated and outlined five hundred years ago, at the height of the Renaissance and the dawn of the modern scientific age." We do get some hints of what that would look like here and there. But mostly it's a biography of Leonardo da Vinci. Which is interesting. It's a nice lens through which to learn Italian renaissance history. But I'm going to focus here on the details that offer a model for a more humane, open-minded science.
Still not sure exactly what that is but Leonardo has some idea about what it isn't:
The abbreviators of works do injury to knowledge and to love... Of what value is he who, in order to abbreviate the parts of those things of which he professes to give complete knowledge, leaves out the greater part of the things of which the whole is composed? ... Oh human stupidity! ... You don't see that you are falling into the same error as one who strips a tree of its adornment of branches full of leaves, intermingled with fragrant flowers or fruit, in order to demonstrat that the tree is good for making planks. (Anatomical studies folio 173r)
The idea that reductive, abbreviated thinking could do violence to something so numinous as love is fairly instinctive. I remember a reviewer of one of Helen Fisher's books quoting Blake: ''He who binds to himself a joy / Does the winged life destroy." I'm an admirer of Fisher's work actually, and I've found her observations on the chemistry of sexual chemistry useful in my life, but I've found Shakespeare's observations on the subject infinitely more useful (also somewhat more entertaining). The idea that abbreviating could injure knowledge is more fraught: we have to zero in on specifics in order to build knowledge. In fact many neuroscientists thing that our brains are primarily filtering devices, selectively screening out the overwhelming static of sensations. With out this abbreviating function I'd be helpless, distracted by the weight and texture of the sweatshirt on my shoulders, conscious of every nuance of traffic noise from Mission Street, acutely aware - not only of how the light and shadow falls on my fern - but of the exact lobed form of each leaf, the number of frond in the business of unfurling, the way the stalks turn from green to glossy purple as they age. And as I've turned my attention to Fernando I've completely lost track of the larger point, which was... oh yeah, that we are all reductionists by necessity, we need a narrow point of focus to penetrate the dermis of reality. And it seems churlish to criticize a Helen Fisher for coming back from the tip of the needle with some very limited new facts. But I don't think that's the kind of abbreviation that Leonardo is complaining about. He did the same thing, by dissecting cadavers he was able to show that certain Medieval theories of the workings of the eye were wrong, and he correctly traced the optic nerve back into the brain, hypothesizing that the impressions from light sent "tremors" through this nerve. Now that's pretty impressive, but it's also reductive and if you leaned to much on it the idea of waves flowing through a hollow nerve could retard advances in understanding electric impulses and neural networks. And how hard one leans on a hypothesis (hypothesis can morph into dogma) may be the thing that determines whether reduction is constructive or destructive. This is a crucial point for me to understand: If abbreviation is the problem but I also want to embrace some forms of reductive science, I need to know exactly where it goes bad.
This book doesn't spell that out, but I will make some notes on Leonardo that may be useful later on.
  • He was self taught - while all the other thinkers were spending their time trying to recover the wisdom of the Greeks (and square it with their own beliefs), Leonardo (who couldn't read Greek or Latin) was trying to figure out how to make things work: How do you forge the biggest-ever sculpture of a horse? How do you defend a city against attack? How do you dispose of human waste in a big city? How do you paint moving water, human faces, rock walls, plants, birds... that look exactly right? And these questions led him to watch things intensely, experiment, dissect, develop the sciences of geology, optics, fluid dynamics. He read everything he could, but he never felt the pressure to shoehorn all his findings into some kind of grand unified theory. He was starting from the real world and working out in every direction rather than building up from a single theoretical foundation.
  • Fitjof proposes that his decoration of the Sala delle Asse (detail above) is emblematic of his science. The room is painted with mulberry trees, with trunks going up the columns and branches braiding across the ceiling arches. The golden ribbon, arranged in traditional knots, Fritjof claims, is an allusion to the "similarities of patterns and possesses" repeated at various scales and places throughout the universe. Rene Descartes also used a tree as a metaphor for science: "The roots are metaphysics, the trunk is physics, and the branches are all the other sciences." Here's Fitjof: "Leonardo's science, by contrast, cannot be reduced to a single foundation... It's strength does not derive from a single trunk, but from the complex interconnectedness of the branches of many trees... numerous patterns of relationships..."
  • Not a big fan of doctors: he wrote this alongside some anatomical drawings (taken from recently dead cadavers remember), " Strive to preserve your health in which you will be more successful the more you are wary of physicians."
  • References back to Aristotle and Plato 148: There's this central dichotomy set up - Platonists, for whom only ides were real and the world of the senses was illusory, and the Aristotelians, for whom the senses provided reality and ideas were mere abstraction." You had followers of Plato in Florence (interested in mathematical precision, abstraction, theory) and Aristotelians in Milan (interested in observation, and qualities rather than quantities). But the dichotomy gets jumbled pretty quickly: Aristotle thought people should gather knowledge by watching nature: "Experiments that altered natural conditions in order to bring to light some hidden properties of matter were unnatural." Which may be a clue to the problem I was thinking about above, since experimentation requires reduction - elimination of complexity and confounders. And as you trace this split forward it gets even messier. On 168 we get to the tension between mechanism and holism, "between the study of matter (or substance, structure, quantity) and the study of form (or pattern, order, quality)." Fritjof puts Aristotle (and Leonardo) in the latter camp, but is he confused? He was just saying that Aristotle was all about observing substance and structure. In the former camp (mechanism) he puts Galileo, Descartes, and Newton. Kant and Goerthe are is in holism league. I wonder if Fritjof here isn't suffering from the false dualism forces thhe choice between rationalism and romanticism (he refers to his own book here). One other note on Aristotle 146 - apparently his "observations of marine life were unsurpassed until the nineteenth century." Not sure how you measure that, but, wow.
  • Fritjof comes out and says what it is he thinks Leonardo prefigured on 159, that modern science keeps showing that everything is connected "and that their essential properties, in fact, derive from their relationships to other things." So in order to understand a single particle, we have to understand every particle, which has forced Fritjof to abandon "the Cartesian belief in the certainty of scientific knowledge and to realize that science can never provide complete and definitive explanations. In science, to put it bluntly, we never deal with truth..." But science can make better and better approximate models.
  • Leonardo talking with a man he'd later dissect: "a few hours before his death, told me that he was over a hundred years old and that he felt nothing wrong with his body other than weakness. And thus, while sitting on a bed in the hospital of Santa Maria Nuova in Florence, without any movement or other sign of any mishap, he passed out of this life.--And I mad an anatomy of him in order to see the cause of so sweet a death." (117) He then gives a textbook description of what 300 years later would be called arteriosclerosis. Then on 170 compares human veins to oranges "in which, as the skin thickens, so the pulp diminishes the older they become."
Just one more thought about injury to love and knowledge once before I sign off. In education injury is done to love of knowledge (philo sophia) when ideas and facts are given to people as abstractions in the Platonic emptiness. It sounds much more interesting to go about learning the way Leonardo did.

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