Problems of Epistemology

The Problem of Essence or the Relationship Between Knowledge and Reality

The Idealistic Line of Thought

As a starting point, we shall once again take the ordinary conception. Its perspective embodies naive realism, which holds that our representations are akin to things, like copies to originals—provided they are true representations; false representations are deemed so precisely because they do not accurately reflect the real. Thus, bodies exist outside of us and move in space; they are extended, impenetrable, possessing form, color, taste, smell, etc.; all of these are absolute qualities that imprint themselves upon our representations through the senses.

With the awakening of reflection, various doubts arise. The senses deceive us—at least at times: a stick immersed in water appears to the eye as broken. The sense of touch corrects this deception. Yet who supervises the sense of touch? A feverish patient sees and hears things that are not there, but for him, these hallucinations are perceptions. A dreamer believes in the reality of what unfolds before him in his dreams. Where is the criterion that would allow us to distinguish hallucinations and dreams from genuine perceptions? The feverish patient does not consider himself ill, and the dreamer has no awareness that he is dreaming; indeed, it sometimes seems to him that this time it is not a dream—that he is flying or finding treasure, and that this is actual reality. Alternatively, abstract thinking, seeking to assert its preference, rises up against sensory perception: movement is inconceivable, argues Zeno; therefore, it cannot be real, lest a body could simultaneously be in a particular location and not be there. Thus, the senses, which present us with representations of movement, deceive us. Plato provides a similar argument: perception represents reality as both arising and passing away, i.e., as existing and non-existing at the same time. Since this is inconceivable, it cannot be real; therefore, the entire sensory view of things is a great deception. Truth exists only in abstract thinking, which, akin to mathematics, deals with unchanging entities.

In modern times, such bewildering questions and dialectical arguments have been supplanted by considerations grounded in the physiology of the senses regarding the nature of normal representation. They have utterly dismantled naive realism. This can be schematically represented as follows: we refer to certain food as healthy and some fruit as delicious. What does this mean? Is health located in the food, or is taste inherent in the apple? Clearly not—this is known to common sense—rather, it resides in the one who consumes it; within the apple, there is only a force that acts upon the sense of taste in a particular way. We call sugar sweet; is the situation different here? Common opinion may have doubts, for sugar is indeed sweet in itself. Certainly, it is sweet; but what does that mean? If one examines the matter more closely, it becomes evident that sweetness only manifests when it comes into contact with the tongue. If it did not taste sweet, one would not say it was sweet. The sensation of sweetness is not inherent in the sugar itself but resides in you; it may possess only a property or force that causes you to experience that taste. Were there no tongue, there would be neither the sensation of sweetness nor that of bitterness—sweetness and bitterness would not exist in the world at all. The same applies to qualities perceived by the eye and ear: were there no ear, there would be no sounds; were there no eye, there would be neither light nor colors. We can attribute only the property or force capable of stimulating the sensory organs in such a way that these sensations arise in consciousness. This force has been discovered by modern natural science; we now know that what elicits the sensation of sound is the wave-like movement of air or another elastic medium; what provokes the sensation of light is the oscillatory movement of ether.

Here, epistemological reflection usually comes to a halt; however, we might further conceive the following: outside of us, in space, exist bodies; they are extended, impenetrable, mobile, endowed with various forces. Yet they do not possess, as properties, the qualities of sensory perception; rather, the latter exist only in the subject, while in objects exist only the forces to stimulate them. Moreover, there is absolutely no similarity between these forces and their effects. Sound is not akin to the air oscillations that excite the auditory nerves; likewise, light bears no resemblance to ether waves; green color is not an imprint of the structure of a body reflecting green rays. The qualities we perceive are merely symbols of the actual, much like letters are symbols of sounds, and words are symbols of representations, but not similar imprints.

This is the standpoint where the epistemological reflection of the seventeenth century comes to rest. Descartes, Hobbes, Spinoza, and Locke converge on the idea that sensory qualities exist solely in the consciousness of the subject; outside of that, bodies exist that provoke these qualities. Locke articulated this viewpoint in his distinction between primary and secondary qualities. Primary qualities are extension, impenetrability, divisibility, and motion; they pertain to bodies themselves, as this is evident from the fact that they are inherent in all bodies, even the tiniest particles, and in all circumstances. Secondary qualities, such as color, taste, smell, etc., are not inherent to bodies themselves but exist only in relation to our sensory faculties. Many physiologists and philosophers still adhere to this perspective today.

I do not believe we can rest here. The distinction between primary and secondary qualities is not sustainable; extension, impenetrability, and motion cannot be absolute definitions of things any more than colors and sounds can. The same reasoning that leads us to attribute secondary qualities to the subject compels us to acknowledge the subjectivity of the so-called primary qualities as well.

Firstly, we arrive at their representation through the same means—via perception or, at the very least, not without perception. Without the senses of sight and touch, one could not discuss extension and impenetrability any more than one could speak of sounds without hearing them. Imagine a person who, from the outset, lacks the sensations of touch and motion in addition to sight, someone who has never felt the movement of his own limbs or the pressure of his surroundings; it would be equally impossible for him to comprehend what a body is as it would be for a blind person to understand what red or blue is. Therefore, corporeality is the content of perceptions.

Then, as in the case of secondary qualities, the following consideration holds true: perception does not passively borrow its content from the external world; rather, it produces it spontaneously. Common opinion tends to view the matter in this way: extension is perceived directly, the eye perceives planar images of extended bodies, and the overall content of space is acquired through abstraction from the extended images of perception. However, some reflection, guided by physiology, reveals the fallacy of this view. An extended image of an object is indeed reflected on the retina, but this image is not perception itself. The latter arises only when the excitations produced by light rays in the terminal organs of the optic nerve on the retina are transmitted by the fibers of this nerve to the brain. What is conducted to the brain is certainly not the image that was on the retina; such images cannot be separated from it, and nerve fibers are incapable of transporting images. Moreover, even if this image could be separated and transmitted in parts through individual fibers of the optic nerve (as through pneumatic tubes) to the brain and then reassembled here, nothing would be gained, as it would still be dark in the brain. Even if light were brought in, the endeavor would still be futile; the eye would again be needed to see this image, and the brain to perceive it. Thus, the extended image, in any case, regardless of how extension stands in the external world, is not perceived from the external world but is produced anew in the event of some excitation, just as sound and color are. The same applies to the sensations of touch; the tactile nerves cannot convey ready-made extended copies of bodies to the brain. Lotze has presented these matters with remarkable persuasiveness in his "Medical Psychology"; individual fibers of the sensory nerve do not transmit extended images to the brain but qualitatively different excitations, based upon which the soul constructs the image of perception. Therefore, we have just as little basis to view extension as an absolute determination or property of things themselves as we do with color or taste.

With this, the objective existence of the body itself collapses. The body, as we must say in accordance with this view, is a subjective formation produced by certain excitations in our mind. At the very least, we have no grounds to assert that something akin to our representation of the body exists outside our world of representations. Extension, impenetrability, motion, as well as odors and tastes, should be regarded as mere symbols of transcendent reality.

The first to recognize and boldly draw this conclusion about the nature of perception was George Berkeley: bodies are ideas, their existence consists in being perceived (esse est percipi). However, an older metaphysical direction, from other perspectives, repeatedly approached this viewpoint; for instance, Spinoza and even more clearly Leibniz, as well as Plato in Greek philosophy—all saw themselves led to the theorem that the spatial world cannot be absolute reality, that extension and divisibility are incompatible with absolute reality. The historical significance of Berkeley lies in his establishment of epistemological idealism as the foundation of metaphysical idealism.

In German philosophy, this perspective was introduced by Kant: the material world or all of nature is a subjectively conditioned world of phenomena. Subsequently, epistemological idealism becomes the point of departure for metaphysical idealism here as well—already to some extent in Kant himself, although his metaphysics, caught between the theory of knowledge and morality, does not attain independent existence; quite decisively, on the other hand, in speculative philosophy, as well as in Schopenhauer, Herbart, and their followers.

It is remarkable, however, that Kant leads his readers to phenomenalism—indeed, it seems he himself arrives there—starting from a different perspective, namely from reflections on the essence of space and time. What is space in itself? Common opinion, considering it to be real in itself, envisions it somewhat as an empty vessel in which things are contained and move. These things could be absent, and yet an empty space would remain, existing as a reality in itself. But the moment one attempts to take this view seriously, a mountain of difficulties arises. What then is this empty space? By what means does something greater than mere nothing exist where there is only empty space? Or what are the walls of this vessel made of? Or does it have no walls at all, being infinite? This is likely so, for it is impossible to conceive of space as limited; each boundary inevitably points to the space beyond it. Now, a vessel that has no walls and about which one cannot even say what it is or how it differs from nothing is a rather strange reality, and Kant is not wrong in calling it "a being that is not a thing" (ein seiendes Unding). The same applies to time, this empty vessel in which all events occur. Here, too, the matter becomes even stranger. Time consists of the past and the future, divided by the moving point of "now." Since the past no longer exists and the future is not yet present, time would be real, made up of two halves that are both invalid.

From all these difficulties emerges, in Kant's view, the one who dares to say: space and time are not real existences; for in that case, they would indeed be beings that are not things but forms of subjective contemplation. Space is the form of external perception, that is, the order of sensations produced by the subject in relation to which all other sensory experiences are arranged. Similarly, time is the form of internal sense. Of course, one cannot conceive of these forms of perception as if they were ready-made empty boxes; they consist only in the function of distributing all elements in relation to one another—a function that is not innate but acquired or developed over the course of life, even if on an inherited basis. In accordance with this, empty space and empty time would be representations of universal possibilities for distributing bodies, movements, and internal phenomena in relation to one another. With this, the aforementioned difficulty of the question of whether space and time are finite or infinite disappears. We shall say: neither finite nor infinite. Just as one cannot say of a series of numbers that it is finite or infinite, since from any point in it one can continue as far as one wishes, so it is with space and time: at any point, it is possible to proceed further in all directions; the possibility of synthesis in space and time meets with no obstacles, just as the possibility of progressive addition does; likewise, analysis does not encounter ultimate parts anywhere, just as division does not.

Kant succinctly summarizes the outcome of his reflections in the following formula: space and time possess empirical reality yet transcendental ideality. For our contemplation, space and time are universal and necessary assumptions; thus, what holds true in relation to space and time holds true for nature, which is nothing other than a space and time filled with phenomena. However, this does not apply to things as they exist in themselves. We have no reason to believe that the order of our sensations represents the absolute order of things-in-themselves. Alternatively, to express this more concretely, we can envision beings that possess different sensory organs and perceptual contents, as well as distinct forms of ordering elements, differing from our own. We can imagine a mind for which concepts of before and after, or inside and outside, hold no meaning or significance. The components of a mathematical proof or calculation do not exist outside one another in space; their symbols and signs may lie apart, but not the factors themselves. Similarly, they are neither before nor after one another; that is, in the consciousness of the one performing the calculations, they appear sequentially, but this is merely incidental; in themselves, they are simultaneous, or rather, do not relate to time at all. In a perfect consciousness, there would exist solely internal logical relationships among the elements, devoid of any spatial or temporal mixture.

Now, let us imagine that things themselves are akin to numbers and that similar internal relationships exist among them as between numbers. In this case, the most profound understanding of reality would be that of a mathematician who comprehensively grasps all these elements and their relationships in a single glance or thought. Furthermore, if we suppose that “to be real” consists precisely in “to be thinkable,” we would arrive at the concept that Kant introduces for orientation: the concept of intellectus archetypus, a creative and non-sensory mode of thinking. Conversely, our knowledge of reality is external and contingent; our mind does not create reality but is stimulated by contact with the present reality, generating sensations that express not so much the nature of things as our own nature. Thus, it does not grasp the intrinsic relationships of things, the internal mathematical-logical or aesthetic-teleological structure of the elements of reality, but instead produces an external, spatial-temporal structure of sensations.

To this view, Kant subsequently adds another perspective, stating that both the forms of our perception and the forms of our thinking hold only empirical, not transcendental significance. Causality and substantiality—these two principal categories—are subjectively necessary forms of organizing our perceptions, yet do not represent forms of existence of absolute activity.

This seemingly leads to an unconditional conclusion of universal phenomenalism: the world of representations is not covered by reality at any point; there is no adequate knowledge of either the external world or the internal.

Let us consider one final step—renouncing things-in-themselves. It is said that Fichte, in this respect, carried Kant's thought to its conclusion. Indeed, things-in-themselves are incompatible with Kant’s premises. Without things-in-themselves, one cannot enter into the system; yet, with them, one cannot remain within it. We are presented with representations—how can we move from them to things-in-themselves? Kant posits that things-in-themselves act upon us. Consequently, according to the law of causality, from sensations as actions, he infers the existence of things-in-themselves as causes. Yet he himself, recognizing that the law of causality possesses only empirical immanence and not transcendental significance, renders such an inference impossible.

This would be the ultimate point to which absolute phenomenalism can advance: the world of my representation is reality itself; beyond these limits, there is nothing.