Self Comes to Mind
intentions, and strategies behind our sophisticated life management. Why should we not? That is a reasonable and parsimonious way of conceiving the history of such processes, when we view it from the top of the pyramid and from present circumstances. The reality, however, is that the conscious mind has merely made the basic life-management know-how, well, knowable . As we shall see, the decisive contributions of the conscious mind to evolution come at a much higher level; they have to do with deliberative, offline decision-making and with cultural creations. I am definitely not minimizing the importance of that high level of life management. Indeed, one of the main ideas in this book is that the human conscious mind has taken evolution in a new course precisely by providing us with choices, by making relatively flexible sociocultural regulation possible beyond the complex social organization that social insects, for example, so spectacularly exhibit. Rather, I am reversing the narrative sequence of the traditional account of consciousness by having covert knowledge of life management precede the conscious experience of any such knowledge. I am also saying that the covert knowledge is quite sophisticated and should not be regarded as primitive. Its complexity is huge and its seeming intelligence remarkable.
I am not downgrading consciousness but am most certainly upgrading nonconscious life management and suggesting that it constitutes the blueprint for attitudes and intentions of conscious minds.
Every cell in our body has the kind of nonconscious attitude I have just described. Could it be that our very human conscious desire to live, our will to prevail, began as an aggregate of the inchoate wills of all the cells in our body, a collective voice set free in a song of affirmation?
The notion of a large collective of wills expressed through one single voice is not mere poetic fancy. It connects with the reality of our organisms where that single voice does exist in the form of the self in a conscious brain. But how does one transfer the brainless, mindless wills of single cells and their collectives to the self of conscious minds that originates in a brain? For that to happen, we need to introduce a radical, game-changing actor in our narrative: the nervous cell or neuron.
Neurons, as far as one can fathom, are unique cells, of a kind unlike any other in the body, unlike even other kinds of brain cells such as glial cells. What makes neurons so different and so special? After all, don’t they too have a cell body, equipped with nucleus, cytoplasm, and membrane? Don’t they rearrange molecules internally as other body cells do? Don’t they too adapt to the environment? Yes, indeed, all the above is true. Neurons are, through and through, body cells, and yet they also are special.
To explain why neurons are special, we should consider a functional difference and a strategic difference. The essential functional difference has to do with the neuron’s ability to produce electrochemical signals capable of changing the state of other cells. Neurons did not invent electrical signals. For example, unicellular organisms such as paramecia can also produce them and use them to govern their behavior. But neurons use their signals to influence other cells, namely, other neurons, endocrine cells (which secrete chemical molecules), and muscle fiber cells. Changing the state of other cells is the very source of the activity that constitutes and regulates behavior, to begin with, and that eventually also contributes to making a mind. Neurons are capable of this feat because they produce and propagate an electrical current along the tubelike section known as the axon. Sometimes the transmission goes over distances that can be appreciated by the naked eye, as when signals travel for many centimeters along the axons of neurons from our motor cortex to the brain stem, or from the spinal cord to the tip of a limb. When the electrical current arrives at the tip of the neuron, the synapse, it causes the release of a chemical molecule, a transmitter, which in turn acts on the subsequent cell in the chain. When the subsequent cell is a muscle fiber, movement ensues. 4
There is no longer any mystery as to why neurons do this. Like other body cells, neurons have electrical charges on the inside and outside of their membranes. The charges are due to the concentration of ions such as sodium or potassium on either side of the wall. But
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