Saturday, July 21, 2007


Most of us who know the least little bit at all about biology (fundie Xtians excused) know that our cells replace themselves. Roughly every seven years, we are “evolved again” (my word). Of course, I didn’t know until Antonio Damasio taught me that the “precious neurons in our brains, the muscle cells of the heart and the cells of the lens” do not replace themselves. (The Feeling of What Happens, p. 144) In his marvelous study of how consciousness evolved, I find a great deal of interesting reading and one fascinating passage is the following one so marvelously poetic about the constant replacement of the body as it ceaselessly reinvents the structure that evolution has given it.

We are not merely perishable at the end of our lives. Most parts of us perish during our lifetime only to be substituted by other perishable parts. The cycles of death and birth repeat themselves many times in a life span—some of the cells in our bodies survive for as little as one week, most for not more than one year; the exceptions are the precious neurons in our brains, the muscle cells of the heart, and the cells of the lens. Most of the components that do not get substituted—such as the neurons—get changed by learning. (In fact, nothing being sacred, even some neurons may get substituted.) Life makes neurons behave differently by altering, for instance, the way they connect with others. No component remains the same for very long, and most of the cells and tissues that constitute our bodies today are not the same we owned when we entered college. What remains the same, in good part, is the construction plan for our organism structure and the set points for the operation of its parts. Call it the spirit of the form and the spirit of the function.

When we discover what we are made of and how we are put together, we discover a ceaseless process of building up and tearing down, and we realize that life is at the mercy of that never-ending process. Like the sand on the beaches of our childhood, it can be washed away. It is astonishing that we have a sense of self at all, that we have—that most of us have, some of us have—some continuity of structure and function that constitutes identity, some stable traits of behavior we call a personality. Fabulous indeed, amazing for certain, that you are you and I am me.

But the problem goes beyond perishability and renewal. Just as death and life cycles reconstruct the organism and its parts according to a plan, the brain reconstructs the sense of self moment by moment. We do not have a self sculpted in stone and, like stone, resistant to the ravages of time. Our sense of self is a state of the organism, the result of certain components operating in a certain manner and interacting in a certain way, within certain parameters. It is another construction, a vulnerable pattern of integrated operations whose consequence is to generate the mental representation of a living individual being. The entire biological edifice, from cells, tissues, and organs to systems and images, is held alive by the constant execution of construction plans, always on the brink of partial or complete collapse should the process of rebuilding and renewal break down. The 
construction plans are all woven around the need to stay away from the brink.

I am doing this at two to three in the morning as the object, George Bush, arising from my memory banks, has chosen to impinge its ghastly presence upon my hapless organism, rendering it alert and sensing danger when it should be replenishing itself with sleep.

PS: Call the tree, raising its arms into the sky, a "forest monster". Does it give you that eerie feeling like forests do in some of these recent children's movies like Harry Potter, those boring, endless Ring tales and that old Wizard of "if you've seen it once, you've seen it a thousand times" Oz?

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