Problems of Metaphysics

Ontological Problem

Critics of Materialism: The Parallelist Theory of the Relationship between the Physical and the Mental

We now turn our attention to a critique of the theoretical value of the materialist theory. Is it truly the case that all that is real consists solely of bodies or the activities of bodies?
I must confess at once that I find it impossible to be convinced of this. While this perspective may suffice for the purposes of natural science, it falls short for a broader construction of reality. A universal or philosophical view of reality is satisfied only by an idealist theory that perceives the truly real as existing in the mental and spiritual realm.

Currently, it has become common, particularly in philosophical circles, to demonstrate the inadequacy of materialism chiefly through epistemological (knowledge-based) arguments. Kant is renowned as the ultimate victor over materialism, as portrayed in F. A. Lange's "History of Materialism." Schopenhauer extols him, claiming he revealed the great truth: there can be no object without a subject; the absurd endeavor of materialism lies precisely in attempting to derive the subject from the object.
I shall not delve deeper into this here; I will return to it when discussing the theory of knowledge. I note only that I share the sentiment that through epistemological considerations, dogmatic materialism can be definitively dismissed. It shows that bodies not only do not constitute the sole absolute reality but also do not possess absolute reality at all; bodies possess only relative existence, specifically existence as phenomena for a correspondingly organized subject. Their entire essence consists in the content of perception; a body is white or black, soft or hard, has shape and extension, occupies space, and resists intrusion into that space—all these attributes pertain to the body in relation to a subject endowed with a certain sensibility and intellectual structure: without language, there is no taste; without an eye, there is no light or color; without sensibility and reason, there is neither space nor body; without a subject, there is no object. This is a thought whose truth must be recognized by anyone who contemplates these matters. Schopenhauer articulates it in one place as a dialogue between the subject and matter, as follows. Matter argues: “I exist, and apart from me, there is nothing. The world is my transient form. You are merely the result of one part of this form and entirely accidental. Just a few moments, and you will cease to exist. I, however, endure from millennium to millennium.” To this, the subject replies: “This infinite time, of which you boast, exists, like the space you occupy, solely in my representation, in which you are presented, which perceives you, by which alone you acquire existence.”
Such a perspective can profoundly impress and may even shake one’s convictions, but it finds it challenging to establish a firm belief. A person encountering it for the first time may easily feel taken aback. He might think, “It is certainly possible to say this, and perhaps it is difficult, or even impossible, to refute these words; however, they do not thereby become truth. It remains true that the world existed before me and my representation, that the sun, moon, and stars, along with the earth, existed long before the eye appeared to see them.” As soon as one’s gaze returns to the realm of perceptual contemplation, the faith that this dense corporeal world is indeed reality and that it exists independently of the representing subject reasserts itself with irresistible force. Like Antaeus, drawing strength from contact with the earth, materialism regains its power through its encounter with perceptual observation. Let this be regarded as the weakness of sound human reason, which falters in abstract thought, and let Meiner be correct in asserting that “one of the most unconditional reactive means to human thought is whether one can or cannot comprehend the non-existence of the world in the forms in which it is created by our mental activity.” However, anyone seeking to foster a genuine conviction of the inadequacy of materialist theory will poorly accomplish their task if they limit themselves to epistemological considerations. Materialism arose and established itself on the grounds of metaphysics or natural philosophy; it is here that one must confront it who wishes to vanquish it. In what follows, we shall thus stand on this ground.

The thesis of materialism, therefore, posits that phenomena of consciousness are likewise functions of matter; they can be physiologically explained as functions of the nervous system, as results of nervous processes. Is this assertion well-founded?
Recently, objections have been raised against this from a physiological standpoint: it is absolutely impossible to explain phenomena of consciousness from phenomena of motion, and ultimately, physiological explanations boil down to precisely this. Du Bois-Reymond has become a widely heard advocate of this objection. In his frequently cited article “On the Limits of Natural Science,” he argues: all physical phenomena, without exception, can be explained physically, and there is no limit to their explainability; there are many things that remain unexplained, but none that are intrinsically inexplicable. There are no fundamental obstacles to the scientific explanation of vital phenomena, including the emergence of the first organisms. However, with the very first element of consciousness, with the most primitive sensation, something arises that unequivocally eludes scientific explanation. “Consciousness cannot be explained from its material conditions.” “The anatomical knowledge of the brain, the highest we can demand of it, reveals to us nothing but moving matter. But no matter what distribution or movement of material particles we devise, we cannot bridge the gap to the realm of consciousness.” He concludes with the emphatic declaration: “In relation to the mysteries of the corporeal world, the natural scientist has long been accustomed to pronounce his ignoramus with courageous self-denial. In light of the victorious path he has traversed, he is supported by the calm awareness that where he currently does not know, he could, at least under certain circumstances, know, and that perhaps one day he will know. In regard to the mystery of what matter and force are and how they can think, he must resolutely decide upon a far more difficult judgment to pronounce: ignorabimus.”
This reflection has been viewed as a refutation of materialism; indeed, it may have intended this. Yet I find it insufficient for this purpose; it does not truly strike at the point where materialism is vulnerable, at least only hesitantly and in passing. The materialist philosopher could respond to this objection as follows: judging by the explanations given, the disputed point between us and the author of “The Limits of Natural Science” lies solely in whether phenomena of consciousness can be explained from material conditions. We affirmatively answer this question; he denies it. Conversely, we completely agree that consciousness is dependent on material conditions; he perceives himself as far above “the dogmas and the proud old-age philosophies” with their faith in a distinct spiritual substance; he believes that “in a thousand cases, material conditions influence spiritual life.”

For his unconstrained gaze, there is no basis for doubting that "sensory impressions are conveyed to the so-called soul" (p. 45), and it occurs to him that the soul arose as a gradual product of certain material combinations (p. 47). When speaking of the Fichtean comparison of thought to the secretion of an organ, he finds nothing deserving of censure in the view that "mental activity appears as a product of the material conditions of the brain." The only error he perceives is the implication that mental activity can be as easily explained in its nature from the structure of the brain as, with sufficient progress in knowledge, one might explain the secretion from the structure of a gland (p. 50). Thus, the stumbling block is not the fact of conditionality, but merely its comprehensibility; we know that movements cause phenomena of consciousness, yet the question of how remains eternally mysterious.

The materialistic philosopher might now continue, saying: here lies the crux of the matter—how molecules begin to think is something we do not know and perhaps may never know. But is there anything particularly exceptional in this? Does a scientific explanation consist anywhere in depicting the course of how a cause produces an effect? Physics explains numerous phenomena through the law of gravitation: the fall of a stone, the flow of a stream, the ascent of a balloon, the ebb and flow of the sea, the movement of planets—all are encompassed under the common formula of the law of gravitation. But does it show how bodies attract each other in general or why they tend to move towards each other according to this formula? Not at all. Similarly, chemistry does not explain why certain elements combine in one way or another, or why they combine at all; it only tells us what, but not how or why. The same holds true for mechanics: it does not explain how one body transfers its motion to another upon collision; it merely subsumes the factual state of affairs under a formula. Thus, to explain any phenomenon in the natural sciences simply means finding the formula under which it is encompassed as a specific case, with which it can be predicted, calculated, and under certain circumstances even invoked. Here, Dubois-Reymond adheres to the same viewpoint: what is force, or where does motion originate from? This, along with the essence of matter, represents a transcendent problem for him as well.

Therefore, concludes the materialistic philosopher, it is unreasonable to expect or demand anything different when it comes to the explanation of consciousness phenomena. In the realm of natural sciences, they will be explained if it becomes possible to formulate principles from which their occurrence can be anticipated in relation to other phenomena, for example, physiological phenomena in the brain. If we were to know that a particular event in the cells and conducting fibers of the brain invariably results in a specific representation or feeling of a certain kind and intensity, then we would know everything we, as scientific investigators, wish to know. The fact that we do not understand how a physiological phenomenon produces a sensation cannot weigh upon us, as long as we remain ignorant of how one movement produces another. However, in principle, there is no obstacle to the eventual achievement of such formulas by the physiology of the brain. Whether we will truly reach this point, whether physiology will ever be able to depict the movements of brain molecules that result in a specific sensation or even a specific thought process, is certainly highly questionable. Yet, if the mere possibility of this is accepted, then the possibility of a physical explanation for consciousness phenomena is acknowledged— in the same sense that the term "explanation" is generally employed in the natural sciences.

Thus, it seems to me, could materialism defend itself against the aforementioned objection. And so, if we wish to make the final point truly incisive, we must express it differently; we must assert, and it is evident that this is indeed its intent: there cannot be formulas that bind physical and mental phenomena in the same manner as the laws of mechanics link the phenomena of motion; in other words, there is no causal relationship between physical and mental phenomena; consciousness phenomena are neither actions nor causes of physical phenomena.

Herein lies, at the very least, the beginning of the end for materialism—though, for now, it is only the beginning.

However, to demonstrate this, it is first necessary to compel materialist philosophers to articulate their assertions more precisely. They typically present various formulas as if they were equivalent. These can be distilled into two primary forms: 1) Consciousness phenomena are actions of physical phenomena. 2) Consciousness phenomena are, in themselves or from an objective standpoint, nothing more than physical phenomena in the brain. These two formulas are continually intertwined by our materialist writers. Thus, Büchner declares that mental phenomena are actions of brain activity: how they arise from material combinations may forever remain a question; it suffices to know that "material movements act through the senses upon the spirit and induce movement in it, and these latter in turn produce material movements in the nerves and muscles." Immediately adjacent is the second formula: "thinking can and should be regarded as a special formula of the general motion of nature, which is as characteristic of the substance of the central nervous elements as the motion of contraction is for muscular substance or the motion of light for the cosmic ether." And this, he continues, is not merely a requirement of logic, but has recently been substantiated through experimental means, specifically through experiments demonstrating that mental processes or thought movements require time for their progression. "From this, it follows that a mental or thought act occurs in an extended, resistant, and complex substrate, and thus such an act is nothing other than one of the forms of motion." The same is proven by the fact that the occurrence of any impression in the brain "immediately raises its temperature, and that instantly." This, therefore, demonstrates that mental activity is nothing other than what occurs between the cells of the gray matter of the brain—a radiation of motion induced by external impressions. Other experiments nearly reveal the nature of this motion—namely, those experiments which show that the electricity produced in the nerves diminishes or completely disappears as soon as the nerve begins to perform any physiological function: this irrefutably proves that nerve force or nerve activity is equivalent to transformed electricity.

Recently, a Danish physiologist has proposed a materialistic theory of affects using the same dual formula. According to common understanding, an affect—such as fear—first manifests as a pure phenomenon of consciousness; this, in turn, generates a series of physiological responses, such as pallor, trembling, and so forth. The physiologist reverses this narrative: the mental movement is not the cause but, rather, the consequence of a bodily phenomenon, specifically a physiological process within the vascular-motor system. Or, in another formulation: mental movement is, in essence, comprised of functional changes within the body. The prevailing view that “the modification of a mental state is an affect—true joy, sorrow—while bodily phenomena are merely secondary phenomena that, although always present, are by themselves inconsequential,” is dismissed. It is then demonstrated that a purely mental affect represents an excessive hypothesis; what “the mother feels mourning the death of her child is essentially fatigue and languor in her muscles, the chill of her bloodless skin, the lack of mental clarity and rapid thought in her brain—all of which can be explained by the consideration of the causes of these phenomena. Remove the bodily symptoms from the frightened individual, allow their pulse to beat steadily, their gaze to be firm, their complexion to be healthy, their movements quick and assured, and their thoughts clear—what, then, will remain of their fear?”

If materialism firmly adheres to the second formulation of its thesis, it becomes irrefutable. The assertion that thoughts are, in essence, nothing more than movements in the brain, and that feelings are simply bodily phenomena within the vascular-motor system, is indeed entirely irrefutable—not because it is true, but because it is utterly nonsensical. Nonsense shares with truth the advantage of being unassailable. A thought that is, in essence, nothing but a movement is akin to iron that is essentially wood. One cannot argue against this; one can only state: when I refer to thought, I mean thought, not the movement of brain molecules; and similarly, when I use the words anger and fear, I denote precisely those feelings and not the constriction or dilation of blood vessels. Even if the latter phenomena occur and will always occur when the former do, they are not thoughts or feelings; they can be turned this way and that as desired, but within movement, there lies no semblance of thought. For the ordinary person knows nothing of brain movement or vascular nerves; rather, they are aware of anger and thoughts, and it is these last that they imply when they speak of them, not some obscure phenomenon known only to physiologists, and even they poorly understand it. Even a physiologist, once their science provides them with more accurate information about these bodily phenomena, would they cease to speak of thoughts and feelings, speaking instead only of what they are in their essence—considered in the present sense or objectively, that is, merely as movements? If they were to fall in love, would they not declare their feelings in terms of love rather than in terms of the corresponding vascular process, or, to use Tyndall's words, in “the right-wound spiral movement in their brain,” believing that they have thus fully conveyed the reality of the situation? Such reasoning is manifestly absurd.

Thus, for any debate to be possible, materialism must first discard the formula: thought is movement. Thought is not movement but thought. It is conceivable, on the other hand, that it occupies some correct and expressible relation to movement. Should experience reveal this, the task would then be to establish the nature of that relationship.

Excluding the relationship of identity, two forms of relationship between physical and psychological phenomena remain conceivable: either a causal relationship or a relationship of mere coexistence in time. Such was the understanding since the 17th century of the two competing theories of the relationship between body and soul: the theory of interaction (influxus physicus) and the theory of occasionalism or parallelism. The choice can only be between these two representations. If I am not mistaken, materialism will now side with the former view: consciousness phenomena are actions of bodily events, while the aforementioned physiological critics lean towards the theory of parallelism, albeit without consistently pursuing this thought.

First, let us fully clarify these two representations. Let us imagine, along with Leibniz, a skull of some animal or human the size of a mill; one could walk within it and observe the phenomena in the brain just as one might observe the movements of mechanisms and the interconnections of wheels in a mill. How would the observer perceive the cerebral process under each of these two representations?

The proponent of the parallelistic theory would evidently expect to see the following: physical phenomena in the brain form a self-contained causal nexus; at no point does any member appear that is not, like every other, of physical nature. Psychological phenomena—representations and thoughts—would remain invisible, just as during the movement of the mill. Imagine someone walking down the street. Suddenly, they are called by name; they turn and approach the caller. A perfect physiologist would construct this phenomenon purely mechanically. He would show how the physical action of sound waves on the auditory organ excites a specific nerve process in the auditory nerves; how this, in turn, spreads to the central organ, causing specific physical phenomena, ultimately leading to the innervation of certain groups of motor nerves, resulting in the turning and movement of the body in the direction from which the sound waves emanated. All these phenomena are enclosed within a continuous physical process. Alongside this, another process occurs that the physiologist, as such, neither sees nor needs to know, but of which he is aware as a thinking individual interpreting his perceptions: the auditory sensations evoke representations and feelings; the person who was called hears their name, turns to see who called them and why, recognizes an old acquaintance, and approaches them to greet them. These phenomena unfold parallel to the physical process without interfering with it; perception and representation do not constitute members of the physical causal chain.

Conversely, if the theory of interaction were correct, the situation would present itself differently. The proponent of this theory would expect that the physical process reveals disruptions at specific points, precisely where members of the causal connection involve psychological phenomena. If nerve movement is the cause of sensation, it must disappear as such and manifest as sensation. The movement of sphere A produces the movement of sphere B—this means: the first movement vanishes and, in its place, a corresponding, equal movement of the second sphere occurs. Any movement produces heat—this means: the movement disappears, and instead, a specific quantity of heat emerges. Therefore, the same must hold true in our case: in place of the vanished movement, there would be a sensation or representation of a certain intensity and quality, serving as its equivalent. However, representation cannot be the object of external observation; representations and feelings, as such, cannot be seen or demonstrated through the observational means of natural science. Therefore, for the physicist, as such, there would be a gap in the causal connection; some member would be missing from the physical process. If our materialistic philosopher disagreed with this, claiming that representation is, on the other hand, also something physical, some form of movement, he would thereby renounce his premise and shift to the side of the parallelistic theory. For if that were so, then the natural scientist, as such, would clearly deal only with the physical process and could entirely disregard the fact that this process is accompanied by a process of consciousness. The equivalent and action of the physical cause would then be precisely the physical action and in no way the sensation as such.

Thus, there are two possible ways of representation; which of these corresponds to reality? This question, pertaining to facts, can only be resolved through experience; both of the aforementioned modes of thought are conceivable in and of themselves.

Has experience provided its resolution in this case? I do not believe anyone would assert that definitive observations have been made, excluding one of these representations and rendering the other inevitable; perhaps such observations may never be made. Observation and experiment are rather powerless regarding those most elusive and convoluted phenomena of organic life.

However, a natural scientist would not hesitate long to choose which representation to favor. He would declare: the analogy of all experience compels him to presume the continuity of physical phenomena. In this respect, the assumption of the transformation of motion not into some other form of itself, nor into potential physical energy, but into something that does not physically exist at all, presents a requirement he cannot satisfy. The transformation of motion or force into thought, into the phenomenon of pure consciousness, would be nothing other than the annihilation of energy from the perspective of scientific observation. Likewise, the emergence of motion from the purely spiritual, for instance, from the representation of something desired, would for the physicist be akin to arising from nothing. Therefore, his resolution is such that he cannot but prefer the theory of parallelism over the alternative that admits a causal relationship. In light of the difficult position posed by this dilemma, perhaps even the materialist philosopher might resolve to adopt the parallel hypothesis. Rather than relinquishing the law of the conservation of physical energy, he would ultimately prefer to abandon the formula that states: phenomena of consciousness are actions of physical organization.

And what, he might say, prevents us from representing them as accompanying phenomena of cerebral processes? The relationship remains essentially the same: spiritual phenomena constitute a mere incidental reflex of physical processes, no longer a result. Indeed, he may even assert that this is, in essence, his viewpoint. The cerebral process is objective; sensation, representation, feeling—these are subjective reflexes. Thus, we read in Büchner: "Thinking and extension are two sides or two modes of manifestation of the same singular essence" (p. 300), "spirit and nature are ultimately one and the same"; "logic and mechanism are one and the same, and reason in nature is also the reason of thought" (p. 127).

In the further exposition, we shall therefore accept the theory of parallelism as acknowledged and develop its implications in the next chapter. I remind you once more that we adopt this theory with one epistemological caveat, namely, that the reality pertaining to both the physical and the psychic does not belong in an identical sense. Furthermore, I shall attempt to demonstrate that reality, in an absolute sense, belongs solely to the psychic world, while the bodily world belongs to it only in a relative sense, as an appearance.

But first, I would like to briefly indicate the historical development of the theory of parallelism. It has already been noted above (p. 59) that it was first expressed in its general contours by Spinoza. Leibniz bent it toward idealism, a course Spinoza could not take, despite certain inclinations in that direction: according to Leibniz, reality, as the physical world, is merely a phenomenon in sensory representation, whereas reason knows the truly real as a system of entities akin to souls (monads). Leibniz also has two advantages: he introduced the concept of the unconscious psychic phenomenon, through which a universal parallelism can truly be established; and he avoids the erroneous application of the parallelism of attributes to resolve the epistemological question regarding the relationship between thought and being, a mistake made by Spinoza. Kant, with his metaphysical worldview, essentially remains on the grounds of Leibnizian metaphysics; yet his critical examination, aimed at substantiating epistemological rationalism, leads him to reduce the psychic aspect of reality to mere phenomenon, bringing us to a purely phenomenalist rationalism. Thus, we arrive at the following sequence: in Spinoza, both aspects are real; in Leibniz, the spiritual aspect is real, while the material is phenomenal; in Kant, both aspects are phenomenal. In speculative philosophy, idealistic metaphysics, which exists in Kant as an undercurrent, resurfaces. Schopenhauer provides a significant turn to the parallelist view by defining the inner side of reality as will: the bodily world is merely the manifestation of what reveals itself in self-consciousness as it truly is—namely, will. In our time, Fechner, drawing on Schelling and Spinoza, has once again developed the parallelist theory purely from a natural philosophical perspective and laid the foundation for his universal psychophysical contemplation. Following in these footsteps is Wundt, but only he allows the epistemological direction to bring forth idealistic views more strongly. Among contemporary psychologists who emerge from this perspective, I would mention Geppert (Psychologie in Umrissen, 2nd ed. 1893), Jodl (Lehrbuch der Psychologie, 1896), and Ebbinghaus (Grundzüge der Psychologie, 1897).

As opponents of the parallelist view and proponents of the theory of interaction, we can name Zigvart, Mach, and Stumpf. Recently, the parallelist theory has been subjected to detailed criticism by Fr. Erhardt (Die Wechselwirkung zwischen Leib und Seele); I do not find that he successfully refuted it; his critique does not adequately engage with the parallelist theory in the form in which it is commonly upheld today, that is to say, in an idealistic sense. If bodies are phenomena, then, of course, they cannot interact with that which exists. But even if we adopt a realistic standpoint, it must remain a rule for scientific inquiry: physical phenomena should be explained from physical causes, and conversely, they may have only such actions as pertain to the physical world. If psychic phenomena cannot be represented as such in external contemplation, then they do not exist for the physicist, as such, and he will object to their inclusion in causal relationships. If they do exist in the sensibly perceivable world, as certain physical phenomena or states, then he will hold onto only this aspect of their existence. The position that all reality, along with its causes and actions, is presented within the physical world appears to me an indispensable assumption of any physical investigation. In this regard, materialism is correct, and this position could be termed the foundational principle of formal or critical materialism. If, in the physical world, actions exist that stem from purely psychic causes and vice versa, then we fundamentally position ourselves on the grounds of spiritism: there exists a reality that is in no way physical yet can still have actions in the physical world. Between these two views, it seems to me, there is no middle ground. Dualism, with two disparate elements of reality—purely physical and purely psychic, which form a singular natural connection—may perhaps be possible in itself; yet I assert here only that natural science is unlikely to ever be inclined toward it; it will always prefer materialism. The philosopher will proceed likewise, but he will, along with Kant, place before materialism such a sign: the bodily world is merely a phenomenon.