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Genesis of a Historical Novel

Sunday, January 01, 2006

the mystery of identity

Earplugs deployed, I was oblivious to the midnight yelling, pot-banging, and horn-blowing (Kimmie woke up for it, of course). I woke a couple of times in the night, and finally at about 6:45 got up. I made coffee and served Kimmie in bed, using her tall "snowman" mug for the last time this season (she put away all her indoor decorations as soon as she got up).

I returned to my notes on identity. Why do I feel such a strong urge to delve into this question? I offer that question rhetorically, since it doesn't really matter whether I understand the urge or not. I follow my quest for knowledge wherever it takes me, trusting that it is pointing me where I need to go.

Today it was leading me toward the psychological aspect of the question. I wound up keying notes from the book Abnormal Psychology by Timothy and Joseph Costello; they provide a good overview of the history of psychological theory and practice. I also keyed notes from a book I bought a couple of days ago at Indigo Books: Microbiology the Easy Way by Rene Fester Kratz, a textbook designed to help microbiology students improve their grades (I've never taken microbiology). Why? I was nudged that way by my reading of Acquiring Genomes by Lynn Margulis and Dorion Sagan, in which the authors brush aside Richard Dawkins's concept of the "selfish gene":

Selfish genes, since they are not "selves" in any coherent sense, may be taken as figments of an overactive, primarily English-speaking imagination. The living cell is the true self, an entity that cannot help creating more copies of itself. The engine of evolution is driven by tiny selves of which we are only half conscious.... A gene alone is only a piece of DNA long enough to have a function. There is no life in a gene. A gene never fits the minimal criterion of self, of a living system....

And what about viruses? Here is what they say:

Some present viruses as the smallest forms of life. But viruses are not alive and indeed they are even, in principle, too small to be units of life. They lack the means of producing their own genes and proteins.

According to Margulis and Sagan, the cell is the unit of life--the smallest living thing. It would then also be, presumably, the smallest potential bearer of an identity. This thought led me to buy the microbiology text.

Not that I regard Margulis and Sagan's opinion in this as anything more than that--an opinion. Saying, for instance, that viruses are too small to be alive begs the question, in my view. They are robust, carry around their own genetic material, and are vigorous "survivors" in nature. It's true they don't eat--they don't need to. For me the more telling question would be: do they have an experience? Are they sentient? We can't know this directly, but their behavior is just like that of other, larger, more complex parasites. They look and act like mosquitoes, ticks, lice, and other such things that also require "hosts" to survive and propagate. Or this: if they are not sentient, how would they behave differently if they were sentient? I suspect a sentient virus would behave exactly the way these supposedly nonsentient ones do.

Last night in the microbiology text I was reading about how bacteria, so-called prokaryotic (non-nucleated) cells, are able to propel themselves by means of whiplike appendages called flagella. Flagella rotate, pushing the bacterium forward as a propeller pushes a boat. Bacteria move toward things that are beneficial to them, such as food. When faced with something harmful, a bacterium can reverse the direction of rotation of its flagellum, which causes the bacterium to rotate in place or "tumble". When it is pointed in some new direction, it goes into forward gear again and resumes forward motion.

If I were a bacterium, and sentient, equipped in that way, that's exactly what I would do.

Some bacteria have a further amazing capability: when environmental conditions become harsh (too cold, hot, or food-deficient), they form "spores", which are simply copies of their single chromosome encased in a tough shell of protein. The spore is released from the cell, able to survive for thousands of years or 20 hours' exposure to boiling water. (Indeed, some believe that spores could survive the cold and vacuum of interplanetary space, allowing life to be propagated between planets.)

Is a spore alive? Only in the way a seed is alive. A bacterium is alive, though: it metabolizes, it reproduces. It moves toward food and away from danger. It is a tiny pocket of metabolizing chemicals contained in an envelope called a plasma membrane; it has an inside and an outside. It is indeed a little self--a little identity.

The thesis of Margulis and Sagan's book is that speciation--the creation of new species--occurs mainly through the acquisition of whole genomes by a species. That is, a creature that was prey, or a symbiont--something that lived on or in one's body--now becomes incorporated in one's body so that the two form a new, more complex organism. The mitochondria that provide the energy for our bodies' cells were at one time, in the distant past, free-living creatures in their own right. They became incorporated in a cell at some point in history, and the result of the merger became a viable, indeed more viable, new organism.

What happened to the selfhood of the component creatures? Does each of my cells have a sense of its own individual existence? What does that mean in terms of identity--theirs and mine?

It's a mystery, and it is absorbing me.


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