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Genuine determinism in action appears to require a set of special conditions, with some variation. Thus, it is not the case that those who insist upon the clockwork and deterministic nature of human action are the only (or the majority of; or the most credible and knowledgeable) proper-thinking and appropriately skeptical scientists. There are indeed definitely deterministic acts, such as ballistic movements. But these appear to require one of two conditions: the first might be a very simple reflex structure, involving no more than the firing of a few neurons and communication between their axons—the structures that connect them. The automatic pulling away of your hand from a hot surface is a consequence of just such a simple structure, which appears substantively deterministic (as well as involuntary—an experiential phenomenon that may be at least sometimes a reliable marker of determinism). A sensory neuron specialized to detect heat passes a message to the spinal cord (located closely enough so that transmission time and, therefore, potential damage due to excess exposure to damage, may be avoided). The spinal cord passes the impulse to a relay neuron, linking the sensory neuron to a neuron specialized for movement—a motor neuron. The impulse from the motor neuron forces a contraction in your upper arm, and you jerk your hand away. That’s very deterministic. It happens in 15/100ths of a second, which is far too fast for higher nervous system processes (such as emotion, let alone thought) to intervene. It’s far too fast even for pain to mediate—as the pain of the heat is not causing the reflex. Instead, the pain kicks in even a few seconds after you have moved your hand, suggesting to you, perhaps, that you don’t repeat the experience (that you update the map you used to guide your actions in that particular territory and situation).
The second of the deterministic conditions appears to emerge when something complex enough to involve higher-order nervous system processes including, say, thought and emotion (as well as complex movement, superseding that possible through mere reflex) has been practised repeatedly, often for hours. This is the determinism that characterizes, say, the expert concert pianist. While the musician sits for hours at his or her keyboard, concentrating intently on each note and phrase, perceiving every note and their relationship to all others throughout the piece, intent on proper phrasing and emphasis, movements of finger and hand and arm are all practiced until an entire neurophysiological sensorimotor structure has been built, arduously, connection by connection, in accordance with the revolutionary hypothesis proposed by Donald Hebb:
Let us assume that the persistence or repetition of a reverberatory activity (or “trace”) tends to induce lasting cellular changes that add to its stability. ... When an axon of cell A is near enough to excite a cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A's efficiency, as one of the cells firing B, is increased.
This idea has been famously paraphrased as “neurons wire together if they fire together.” In reality, the neurological situation is more complex. The brain is not a homogeneous mass of neurons, all equally likely to communicate. It appears, instead, that it is a structure of probable highways and superhighways composed of neurons likely to begin coordinating rapidly, if the reason arises, as it is highly likely to (the existence of these highways and superhighways being a consequence of the reactions necessary by the typical human being to the typical environment encountered over the generations of successful survival that have made us what we are: neither the raw and random unstructured jumble of neurons that the brain merely could be, if all learning was unprepared, nor the strict predictable and deterministic response that would be the case if all the wiring was prepared, a priori. This makes sense: the brain, like the body, is a combination of what has been prepared over the expanse of evolutionary time with variability built in to account for what is unique and sometimes radically unique about the seconds, days and years of each particularized lifetime.
But the upshot is this: for there to be true determinism, then the mechanisms that act deterministically must be in place for reflex-like action more complex than the basic reflexes we already discussed to sequence themselves automatically. A pocket watch ticks itself entropically, predictably, into stasis, keeping time as it does so, and it does it predictably. But all the gears and springs are already ordered so that deterministic action can take place. Deterministic action in the nervous system requires the same: the existence of a full-fledged mechanistic system that can transform far-from-simple perceptual input “A” into deterministic but often exceedingly complex output “B”. There isn’t much differences from this and “knowing how to do something” (except that true know-how often retains an element of jazz-like-improvisation about it, as each situation has enough unique about it to require a certain novelty of response, even when encountered many times, by well-practiced experts). It is also the case that the rather simply deterministic if-then “expert” systems frequently produced in the 1980’s, for example, could not describe the current world well enough (regardless of the sophistication of the built-in “expertise”) to determine what should be done next. Mere algorithms—deterministic decision trees or formulas, built in and entirely predictable—proved nowhere near complex to solve complex problems such as the diagnosis of illness. Modern AI systems, which tend to rely on “rules” that are neither observable to nor comprehensible to outside observers, perform such tasks much more reliably—but we don’t understand how they work and cannot build them from the bottom up.
It looks very much like whatever constitutes consciousness is at work when the mechanisms for deterministic and efficient action are not available. This is obvious, experientially, to anyone familiar with learning to drive an automobile. In the early, awkward stages, everything must be attended to, consciously—perceived and acted upon in an exhausting, awkward and dangerous manner. How much pressure to apply to the brake, or the gas pedal; when to begin cornering at what speed when considering a turn; how to perceive the car itself on the correct side of the road: how far to look ahead at what speed: all this must be learned, before it can become anything approximating automatic and deterministic (which might be regarded as the goal). Consciousness is not driven by the past: it apprehends the multiple possibilities of the future, sorts them into what is opportunity and obstacle—desirable and undesirable—practices aiming and the former and avoiding the latter and, through repetition, producing automatized, deterministic sensory-motor structures. And even when practice has made perfect, consciousness looks far enough down the road so that automatized structures are ready, at hand, but so that a choice between which structures will be disinhibited and engaged automatically will be still possible.
It is in keeping with such observations that elites, experts and novices do not use the same brain networks when conducting their motivated actions. It’s that fact that differentiates them. Novices manifest “broad activity” in multiple brain areas. They’re literally all over the place, when they’re learning their task. “The more localized neural activity of elite and expert archers,” by contrast, permits “greater efficiency in the complex processes subserved by these regions.” London cab drivers, who must come to to know the city in great detail, show substantive changes in hippocampal function (a brain area associated with the movement of short term attention into long term memory), indicating the greater extent of their temporal-spatial maps. Expansion of the cerebellum, a large neural structure, responsible at least for coordinating comple activities, characterizes rock climbers, basketball players, and short-track speed skaters, among others. This all fits a more fundamental hypothesis very well: the novelty-routinization principle of brain organization, pioneered by Elkhonon Goldberg, student of the great Russian neuropsychologist Alexander Luria, who produced some of the first reliable work on specialized brain function. It was Goldberg who posited, roughly, that the left hemisphere was specialized for what had become more practiced and specialized (deterministic, if you will), but that the right was specialized for the unpredictable and unexpected and novel. Goldberg’s work (which finds its reflection in Ian McGilchrist’s more recent The Master and his Emissary, as well as in my first book, Maps of Meaning) maps very well on to the idea that reality is reasonably conceptualized as a combination of order (the repetitive and predictable) and chaos (the unpredictable and novel)—given that our very neural structures, which have have hypothetically been shaped over great periods of time by the structure of the real itself, have evolved to reflect that fact.
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