Lost Souls: The Philosophic Origins of a Cultural Dilemma

Chapter Five The Cogito’s Demise

Chapter Five The Cogito’s Demise 1. Mind’s Reduction to Body Descartes established the cogito as the foundation for all Being, but then told us how to subvert it. The means lie directly above the divided line in figure 2.1. Aristotle and medieval physics reconceived Plato’s Forms as myriad qualitative essences (of dog, cat, sheep, and goat, for example). Descartes reduced these differences to three modes of space—magnitude, figure, and motion—by extending the mathematicals to include all the lesser Forms (all but the Good). Kinematics (sometimes with dynamics) was to supply exhaustive explanations for all physical properties and their alterations. Is there a limit to this program for showing that phenomena are explicable in exclusively physical (geometric) terms? Descartes usually insisted that consciousness, self-consciousness, thought, and will (the power of judgment) are mental, never bodily. His critics were less sure that matter cannot think.1 Even Descartes conceded that some mental activities—perception and memory, for example—have bodily origins. And all the while, he encouraged research in micro-physiology: “Now I shall not pause to describe the bones, nerves, muscles, veins, arteries, stomach, liver, spleen, heart, brain, or any of the various other parts. . . . As for the parts which are too small to be seen, I can inform you about them more easily and clearly by speaking of the movements which depend on them.”2 Descartes once remarked that there may be no activities that cannot be performed by bodies: the human machine can “imitate all the movements of real men,”3 including, presumably, the internal movements of the nervous system. This physicalist hypothesis (qualified in 81 82 LOST SOULS Descartes’ other writings) is all but comprehensively confirmed. Mind is a natural and organic phenomenon, though activities such as thought are realizable in various ways (the figure–ground, gestalt thinking of human problem-solving differs, for example, from the exhaustive computer searches of logical trees). Consciousness, too, may have alternative physical expressions and conditions (hierarchically arranged neurons, or silicon chips). Either way, mind is not an extra-natural domain or standpoint. Mental states that are prior in knowledge—as consciousness is better known than brain—are not prior in being. Descartes’ foundationalism loses its base when his psychocentric ontology is empirically refuted by physiologists and engineers who confirm that mind is only material. Physiological techniques—using brain imaging , for example—augment the evidence that machines represent and remember their inputs, calculate, and alter their behaviors in ways appropriate to plans that are revised when frustrated. Refutation is not fully accomplished, because the luminous sense of awareness and the qualitative diversity of its contents (colors and sounds, for example) are not yet explained in physical terms. The understanding and physical reproduction of some principal activities—representation, calculation, and memory—have, nevertheless, altered the question at hand. Descartes supposed that consciousness with self-awareness is the necessary condition and crucible for these activities. (Having ideas requires that awareness be passive and active, if ideas are presented, then inspected. Calculation implies self-awareness, if mind performs an inference by applying a logical rule while scrutinizing its application to guarantee that no mistake has been made.) Now, when thought is reconceptualized as the rule-governed sequencing of thoughts or words, consciousness seems incidental: we think without inspecting every thought or word, and sometimes without being aware that we think. These developments have this odd effect: some Cartesians distinguish consciousness from activities that were once thought impossible to perform without it. They concede that cognition has necessary and sufficient physical conditions, so that consciousness—especially the awareness of sensory data or feelings—is the residual, epiphenomenal, but irreducible, justification for their dualism.4 This is the shrinking perimeter around a collapsing defense. Aristotle’s dictum—that mind is the activity of a body having a certain complexity5—is still a trajectory, not yet a finished achievement. But most of the principal questions are settled: it is not a contradiction that bodies think. Dualists sometimes hope to save their position with semantical arguments about the ostensive meaning of mind, thought, feeling, or awareness; but these are gestures, reminiscent of equally desperate THE COGITO’S DEMISE 83 vitalist arguments about the meaning of life. Neither saves the phenomena signified by the words from a comprehensive explication in physical terms, because the words have been reconceived: each signifies a complex of three factors: the function performed by the relevant...