I. Traditional Epistemologies

Epistemological studies have been carried out since ancient times. It was only in the modern period, however, that epistemology became a central theme of philosophy. The philosopher who first explained epistemology systematically was John Locke, whose An Essay Concerning Human Understanding became known as an epoch-making work.

The most important questions with regard to the cognition of an object have been those of the origin, the object, and the method of cognition, each of which has two opposing positions. In terms of the origin of cognition, two opposing schools of thought have arisen: empiricism, which asserted that cognition could only be obtained through one’s sensations, and rationalism, which asserted that cognition could be obtained only through one’s thinking about ideas, innate in the mind. With regard to the object of cognition, two views have come into opposition: realism, which asserted that the object of cognition existed independently from the human being, and subjective idealism, which asserted that the object of cognition was merely those ideas or representations present in the mind of the subject. Concerning the method of cognition: the transcendental method and the dialectical method were both proposed.

Let me offer a brief review of some major historical developments in the realm of epistemology. As the conflict between empiricism and rationalism developed, empiricism finally fell into skepticism, and rationalism lapsed into dogmatism. Immanuel Kant made an effort to synthesize these two opposing positions by means of his critical method, or transcendental method. This was his theory of an “a priori synthetic judgment,” which holds that the object of cognition is synthesized by the subject. Later, plagiarizing Hegel’s dialectic materialistically, Marx presented his materialist dialectic. Epistemology based on the materialist dialectic is Marxist epistemology, or dialectical epistemology. This is a “copy theory,” or “reflection theory,” which asserts that the content and form of cognition are no more than reflections on the mind of things in the external world.

I would like to clarify at this point that it is not my intention to introduce in any concrete or academic detail the contents of traditional epistemologies. This section is presented simply for the readers’ reference; I will introduce briefly the relevant problems in a traditional epistemology for the sole purpose of showing how the Unification epistemology is able to solve the unresolved problems of traditional epistemologies. Therefore, in terms of an understanding of the Unification epistemology itself, this section can be skipped.

1. Origin of Cognition

Empiricism holds that all knowledge is obtained from one’s experience, whereas rationalism claims that true cognition can be gained only through the operation of one’s reason, independently from experience. During the seventeenth and eighteenth centuries, empiricism was advocated in Great Britain, and rationalism was advocated in continental Europe.

1.1. Empiricism

a) Bacon (1561-1626)

Francis Bacon established the foundation for empiricism. In his renowned work, Novum Organum (1620), he considered traditional learning to be merely a series of useless words, empty in content, and that correct cognition is obtained through observation of nature, and experimentation. According to him, in order to obtain correct cognition, one must first renounce one’s pre-conceived prejudices. As prejudices, he listed four Idols (idola).

The first is the Idols of the Tribe. This refers to the prejudice into which people in general are likely to fall, namely, the prejudice whereby the real nature of things are reflected distortedly, because the human intellect is like an uneven mirror. An example is the inclination to view nature as personalized. The second is the Idols of the Cave. This prejudice arises due to an individual’s unique nature, habits, or narrow preconceptions as if one were looking at the world from inside a cave.
The third is the Idols of the Market Place. This refers to the kind of prejudice that derives from one’s intellect becoming influenced by words. For example, words may be created for things that do not exist, which could lead to empty arguments.
The fourth is the Idols of the Theatre. This is the prejudice that arises from blindly accepting authority or tradition. In other words, it is the prejudice that arises from relying on an authoritative thought or philosophy.

Bacon said that we should first remove these four Idols, and then observe nature to find the essence within each individual phenomenon. For that end, he proposed the inductive method.

b) Locke (1632-1704)

John Locke systematized empiricism, and in his major work, An Essay concerning Human Understanding, he developed his views. Locke denied what Descartes called “innate ideas,” and considered the human mind to be like a blank sheet of paper (tabula rasa): All the ideas coming into the mind are drawn on the blank paper of the mind just as a picture or letters are drawn on a white paper. Thus, all ideas come from experience.

Ideas come into the mind from two sources: one source is sensation, and the other is reflection. For Locke, experiences through sensation and reflection are the origin of cognition. Sensation refers to one’s ability to perceive external objects through one’s sense organs. The ideas of yellow, white, hot, cold, soft, hard, bitter, sweet, and so on, derive from sensation. Reflection refers to our perception of the operations of our mind such as thinking, doubting, believing, reasoning and willing.
Ideas consist of “simple ideas” and “complex ideas.” Simple ideas are those obtained individually and separately from sensation and reflection. When simple ideas become higher ideas through combination, comparison and abstraction under the operations of our understanding, they become complex ideas.

Simple ideas include those with objective validity, namely, solidity, extension, figure, motion, rest, number, and the like; in addition, simple ideas include qualities with subjective validity, namely, color, smell, taste, sound, and the like. The former qualities are called “primary qualities,” and the latter are called “secondary qualities.”

There are three kinds of complex ideas, namely, mode, substance and relation. Mode refers to an idea expressing the state or quality of things, that is, the attributes of things, such as the mode of space (distance, immensity, figure), the mode of time (succession, duration, eternity), the mode of thinking (perception, recollection, contemplation), the mode of number, and the mode of power. Substance refers to an idea concerning the substratum that carries the various qualities. Finally, relation refers to the idea that comes into being by comparing two ideas, like the ideas of cause and effect, identity, and diversity.

Locke regarded knowledge as “the perception of the connection and agreement, or disagreement and repugnancy of any of our Ideas.” He also said, “Truth is the marking down in Words, the agreement or disagreement of Ideas as it is.” He sought to answer the question concerning the origin of cognition by analyzing ideas.

Locke considered certain the existence of the spirit, which is recognized intuitively, and the existence of God, which is recognized through logical proof. But he considered that there can not be certain regarding the existence of material things in the external world, because they can be perceived only through sensation.

c) Berkeley (1685-1753)

George Berkeley rejected Locke’s distinction between primary qualities and secondary qualities, and described both primary and secondary qualities as subjective. For example, distance seems to exist objectively as extension; namely, it seems to be an idea of the primary qualities. According to Berkeley, however, it is a subjective idea. The idea of distance is obtained as follows. We perceive a certain object from a distance with our eyes, and then we approach it and touch it with our hands. When we repeat this process, a certain visual sensation leads us to expect that it will be accompanied by certain tactile sensations of walking. Thus arises the idea of distance. In other words, we do not look at distance as extension itself.

Locke affirmed substance as being the carrier of qualities, but Berkley rejected this view and instead, viewed things as being mere collections of ideas. He asserted that “to be is to be perceived” (esse est percipi). Thus, Berkeley denied the existence of the substance of material objects, but he had no doubt as regards the existence of spirit as the substance that perceives.

d) Hume (1711-76)

David Hume developed empiricism to its logical conclusion. He considered our knowledge as being based on “impressions” and “ideas.” An impression is a direct representation based on sensation and reflection, whereas an idea is a representation that appears in the mind through memory or imagination, after the impression has disappeared. Impressions and ideas make up what he called “perceptions.”

Hume enumerated resemblance, contiguity, and cause and effect as the three laws of the association of ideas. He held the cognition of resemblance and of contiguity as being certain and posing no problem, but there is a problem with cause and effect, he said. With regard to cause and effect, Hume gave the following example: when one hears thunder after a bolt of lightning, one usually thinks that the lightning is the cause and the thunder the effect. Hume, however, claimed that there is no reason to connect the two as cause and effect, for they are merely impressions; the idea of cause and effect is established on the basis of people’s subjective customs and beliefs, he asserted. As another example, the phenomenon of the sun rising shortly after a rooster crows is empirically well known. But we can not say that the rooster’s crowing is the cause, and the sun’s rising is the effect. Knowledge accepted as cause and effect is thus based on subjective human customs and beliefs.

In this way, empiricism, with Hume, became transformed into skepticism. Concerning the idea of substantiality, Hume, like Berkeley, doubted the existence of substance in material objects. He went even further by doubting the very existence of the spiritual substance, considering it to be nothing more than a bundle of perceptions.

1.2. Rationalism

In contrast to empiricism, which developed in Britain, and discussed above, rationalism expanded over continental Europe, represented by Descartes, Spinoza, Leibniz, Wolff, and others. Rationalism held that it is not through our experience that we can obtain correct cognition, but only through our thinking. Correct cognition can be obtained only through deductive logical reasoning. This is the position of Continental rationalism.

a) Descartes (1596-1650)

René Descartes, regarded as the founder of rationalism, began by doubting everything, as a method of obtaining true knowledge. This technique has been called “methodic doubt.” Descartes believed that our sensations can deceive us, and so he doubted everything related to sensation. Why did he adopt such a method? He did so in order to obtain genuine truth. If there remains something that can not be doubted after we have doubted the existence of all things in the world and even ourselves, it is because it is indeed truth. Thus, he doubted everything. As a result, he came to realize that there is one thing which can not be doubted: the fact that I am engaged in the act of doubting. Hence, he established his famous proposition, “I think; therefore, I am” (Cogito, ergo sum).

For Descartes, the proposition “I think, therefore I am” is the first principle of philosophy. That proposition is certain, he argued, because one’s perception of it is clear and distinct. He then derived the general rule (the second principle) that, “things we perceive very clearly and very distinctly are all true.” “Clear” implies that something is present and obvious to the spirit, and “distinct” implies that it is distinguishable from other objects. The opposite of “clear” is “obscure,” and the opposite of “distinct” is “confused.”

The existence of the spiritual substance, an attribute of which is thought, and the existence of the material substance, an attribute of which is extension, can be recognized as certain. In other words, the Cartesian dualism of matter and spirit is established from the first and second principles: The existence of mind (thought) is proved from the first principle, and the existence of matter (extension) is proved from the second principle.

In order to guarantee a clear and distinct cognition, one must not allow cases in which evil spirits secretly deceive people. In order to prevent such a thing, one must assume the existence of God. If God exists, no mistake can occur in our cognition, because the honest God can never deceive us.

Descartes is said to have proved the existence of God as follows: First, the idea of God is innate within us. In order for this idea to exist, the cause of this idea must exist. Second, the fact that we, who are imperfect, have the idea of a perfect Being proves the existence of God. Third, since the idea of the most perfect Being necessarily contains existence as its essence, the existence of God is proved. In this way the existence of God was proved. Therefore, God’s essences, namely, infinity, omniscience, and omnipotence, become clear; honesty (veracity), as one of God’s attributes, is secured. Accordingly, clear and distinct cognition is guaranteed.

Descartes ascertained the existence of God and the existence of spiritual and corporeal substance, or mind and body; among these, the only independent being, in the true sense, is God, for mind and body are both dependent on God. Descartes also held that mind and body―with the attributes of thought and extension, respectively―are substances independent from each other; thus, he advocated dualism. Descartes proved the certainty of clear and distinct cognition, thereby asserting the certainty of rational cognition based on the mathematical method.

b) Spinoza (1632-77)

Baruch de Spinoza, like Descartes, thought that truth can be cognized through rigorous proofs, and tried to develop logical reasoning, particularly by applying the geometrical method to philosophy. The premise of Spinoza’s philosophy was that all truth can be cognized through reason. That is, when one perceives things “in their eternal aspects” (sub-specie eternities) through reason and also perceives them wholly and intuitively in their necessary relationship with God, true cognition can be obtained.

To perceive things “in their eternal aspects” means to understand all things in the process of necessity. Let me explain. When we look at things from such a standpoint, we need not be attached to or disturbed by transient things or passing phenomena, but rather we can come to comprehend things, phenomena, and even ourselves as being expressions of God’s eternal truth, hence, as precious things. Then, we can reach our perfection, and obtain true life, boundless joy, and true happiness. This is what is meant by perceiving things in their eternal aspects. Such perception can be obtained through clear and distinct reason and our spiritual sense.

Spinoza divided cognition into three types: imagination, scientific knowledge (which is on the level of reason), and intuitive knowledge. Among these three, he held that if imagination is not properly ordered by reason, it is imperfect. He thought that true cognition can be obtained through scientific knowledge and intuitive knowledge. For Spinoza, intuitive knowledge is not separated from reason, but rather it is based on reason.

Descartes considered mind, with thought as an attribute, and body, with extension as an attribute, to be substances independent from each other. In contrast, Spinoza held that God alone is substance; and that both extension and thinking are God’s attributes. Spinoza asserted that God and nature are in the relationship of natura naturans (the origin of all things) and natura naturata (everything which follows, by necessity, from the nature of God), and are inseparable. Thus he developed a pantheistic thought, claiming that “God is nature.”

c) Leibnitz (1646-1716)

Gottfried Wilhelm von Leibniz placed great importance on the mathematical method, and considered that the ideal was to derive every proposition from a few fundamental principles. He classified truth into two kinds: first, there is truth that can be arrived at logically through reason, and second, there is truth that can be obtained through experience. He labeled the former as “eternal truths,” or “truths of reason,” and the latter as “truths of fact,” or “contingent truths.” He held that that which guarantees truths of reason is the principle of identity and the principle of contradiction, and that which guarantees truths of fact is the principle of sufficient reason, which says that nothing can exist without sufficient reason.

Yet, such distinctions among kinds of truths apply only to the human intellect. This is because God can cognize, through logical necessity, even that which is regarded by humans as truths of fact. Therefore, ultimately, truth of reason was held to be the ideal truth.

Leibniz also held that the true substance is the “monad,” or a living mirror of the universe. He explained the monad as being a non-spatial substance having perception and appetite, whereby apperception arises as a collection of minute unconscious perceptions. Monads were classified into three stages: sleeping monads (or naked monads) in the material stage; souls (or dreaming monads) in the animal stage, possessing sensation and memory; and spirits (or rational souls) in the human stage, possessing universal cognition. In addition, there is the monad on the highest stage, which is God.

d) Wolff (1679-1754)

Based on Leibniz’s philosophy, Christian Wolff further systematized the rationalistic position. Yet, in the process of this systematization, Leibniz’s original spirit was lost or distorted, and so the main part of Leibniz’s theory is missing from Wolff’s system. Especially, the theory of monads and the doctrine of pre-established harmony were distorted. Kant belonged to the Wolffian school at first, but later strongly criticized him as representative of rational dogmatism.

Wolff held that true knowledge is the truth of reason, derived logically from fundamental principles. He proposed that all truths be established solely on the basis of the principles of identity and contradiction. He accepted the existence of empirical truths as fact, but according to him, truths of reason have nothing to do with empirical truths, and empirical truths are not necessarily true, but only contingently so. In this way, Continental rationalism attached little importance to the cognition of facts, considering that everything must be cognized rationally, and ultimately ended in dogmatism.

2. Essence of the Object of Cognition

We must next consider the question of the object of cognition. Realism asserts that the object of cognition exists objectively, and independently of the subject, whereas subjective idealism states that the object of cognition does not exist in the objective world, but exists only as an idea within the consciousness of the subject.

2.1. Realism

Realism is a general perspective, which includes naive realism, scientific realism, idealistic realism and dialectical realism. Naive realism, also called natural realism, is the common-sense view that the object is composed of matter and exists independently from the subject; moreover it exists just as we see it. In other words, our perception is a faithful copy of the object. Scientific realism is the view that the object exists independently of the subject, but sensory cognition, as it is, is not necessarily true. True existence can be correctly known only by adding our scientific reflection to the empirical facts already obtained from the object, and this is done through the function of understanding, which transcends mere sensory cognition.

For example, the sense of color is a visual phenomenon. Science examines this phenomenon and clarifies that color (say, red color) is the sensation caused by an electromagnetic wave with a definite wavelength. Also, lightning and thunder which are sensed by our eyes and ears are regarded as caused by the electrical discharge taking place in the air. Thus, scientific realism adds scientific reflection to the common-sense view of realism.

Idealistic realism, which is also called objective idealism, is the view that the essence of the object is spiritual and objective, transcending human consciousness. Specifically, this view holds that the spirit not only exists in human beings, but existed at the origin of the world even before the appearance of humankind, and that this original spirit is the true reality of the world, and is the prototype of the universe. In this view, all things are the various expressions of the spirit. For example, Plato regarded Ideas, which are the essences of things, as true reality, and asserted that this world is nothing but the shadow of the world of Ideas. Hegel asserted that the world is the self-development of the Absolute Spirit.

Dialectical materialism holds that an object exists independently of human consciousness, and that it is an objective reality that is reflected in our consciousness. Thus dialectical materialism, also, is realism. It asserts that cognition is the reflection from things outside, on human consciousness, just as things are reflected in a mirror. It does not, however, assert, as does naive realism, that an object exists as it is reflected on the subject’s consciousness; rather, it asserts that true reality can only be cognized by verification through practice. That is the position of the dialectical epistemology, namely, Communist epistemology.

2.2. Subjective Idealism

Realism, as was mentioned, views the object of cognition as existing independently from the subject, whether the object is a material being or an idea. Subjective idealism, on the other hand, holds that the object does not exist independently of the human mind and that its existence can be recognized only to the extent that the object appears in the human mind. Berkeley was its representative exponent, and his proposition “to be is to be perceived” (esse est percipi) eloquently expresses this position. In addition, Johann G. Fichte (1762-1814) held that no one can ever say for sure whether or not non-ego (the object) exists apart from the function of ego, and Arthur Schopenhauer (1788-1860) said “The world is my representation” (Die Welt ist mein Vorstellung), both taking similar positions.

3. Epistemologies in Terms of Method

As we have seen, empiricism, which saw experience as the origin of cognition, developed into skepticism, whereas rationalism, which saw reason as the origin of cognition, developed into dogmatism. They reached these conclusions because they did not examine the questions of how experience becomes truth, and how cognition is made through reason, in other words, the method of cognition. It was Hegel, Marx and Kant who attached importance to the method of cognition. I will introduce here the main points of the Kantian and Marxian methods.

3.1. Kant’s Transcendental Method

British empiricism fell into skepticism, and Continental rationalism fell into dogmatism, but Immanuel Kant (1724-1804) synthesized these two positions and established a new viewpoint. He considered empiricism to be mistaken because it ascribed cognition to experience, disregarding the function of reason, whereas on the other hand, rationalism was mistaken because it regarded reason as almighty. Thus, Kant held that in order to obtain true knowledge, one has to start from an analysis of how experience can become knowledge. To achieve this, one has to examine, or critique, the function of reason.

Kant wrote three books of critique, namely, Critique of Pure Reason, Critique of Practical Reason, and Critique of Judgment, which, respectively, deal with how truth is possible, how good is possible, and how judgment of taste is possible. Accordingly, Kant dealt with the realization of the values of truth, goodness, and beauty. Among his works, the one concerned with epistemology is his Critique of Pure Reason.

Main Points of the Critique of Pure Reason

Kant tried to unify empiricism and rationalism on the basis of the fact that knowledge increases through experience, and that correct knowledge must have universal validity. It is self-evident that cognition starts from experience. Then, Kant proposed that there existed within the subject of cognition “certain a priori forms of cognition.” In other words, the object of cognition is established when the sense content (which is also called material, sensation, manifold of sense, or sense data) coming from the object is put in order by the a priori forms of the subject.

All former philosophies had held that the object is grasped as it is; in contrast, Kant said that the object of cognition is actually synthesized by the subject. Through this insight, Kant believed he had effected a Copernican revolution in philosophy. Thus, Kant’s epistemology did not seek to obtain knowledge of the object itself, but sought to clarify how objective truthfulness might be obtained. He called it the “transcendental method.”

For Kant, cognition is a judgment. A judgment is made in terms of a proposition, and in a proposition there are subject and predicate. Knowledge increases through a judgment (a proposition), in which a new concept that is not contained in the subject appears in the predicate. Kant called such a judgment a “synthetic judgment.” In contrast, a judgment in which the concept of the predicate is already contained in the concept of the subject is called an “analytical judgment.” Hence, new knowledge is obtained only through a synthetic judgment.

Among the examples given by Kant of analytical and synthetic judgments, there are the following: the judgment that “all bodies are extended” is an analytical judgment, for the concept of body already includes the meaning that it has extension. On the other hand, the judgment that “between two points, the straight line is the shortest line” is a synthetic judgment, for the concept of a straight line indicates only the feature of straightness without containing the quantity of length or shortness. Therefore, the concept of the shortest line is a completely new addition.

Yet, even though new knowledge can be obtained through synthetic judgment, it can not become correct knowledge if it does not have universal validity. In order for knowledge to have universal validity, it should not be merely empirical knowledge, but should have some a priori element independent of experience. That is, in order for a synthetic judgment to have universal validity, it must be an a priori cognition, namely, an a priori synthetic judgment. So, Kant had to cope with the question: “How are a priori synthetic judgments possible?”

Content and Form

Kant tried to accomplish the synthesis of empiricism and rationalism through the unity of content and form. “Content” refers to the representations given to our senses through the stimuli from the things in the external world, namely, the content of our mind. Since the content is material coming from the outside, it is an a posteriori, empirical element. On the other hand, “form” refers to the framework, or determinative, that synthesizes or unifies the material, or the manifold of sense. It is the framework that unifies various materials formed in the stage of sensation. In other words, sense content is synthesized by a priori forms. A priori forms consist of the forms of intuition that arrange the manifold of sense in the frame of time and space, and the forms of thought that gives the frame to cognition in the stage of understanding. He argued that, through these a priori forms, synthetic judgments with universal validity become possible.

The forms of intuition are frameworks that perceive the manifold of sense in space and time. Cognition, however, does not take place through intuition alone. Kant said that it is necessary for the object to be thought through understanding, and asserted that a priori concepts, the forms of thought, exist within understanding. In other words, he held that cognition takes place when the content, which is perceived intuitively, and the forms of thought are combined. Kant described it in the following way: “Thoughts without content are empty; intuitions without concepts are blind.” Kant named the a priori concepts within the understanding “pure concepts of understanding” or “categories.” Based on the judgment forms used in general logic since Aristotle, Kant derived the following twelve categories:

In this way, Kant asserted that cognition becomes possible as the sense content is perceived through the forms of intuition and is thought through the forms of thought (categories). Yet, the sense content in the stage of sensation and the forms of thought in the stage of the understanding are not combined automatically. Sensation and understanding are both faculties of cognition, but they are essentially different. A third force common to the two faculties is necessary. That is the power of imagination (Einbildingkraft), with which sense content and the forms of thought are unified, whereby fragmented manifold of sense is synthesized and unified.

Thus, the object of cognition, as Kant says, is the result of the synthesis of the sense content and the forms of thought through the power of imagination. Hence, the object of cognition is not what exists objectively in the external world, but rather it is synthesized in the process of cognition.

We can understand, therefore, that the object of cognition, as Kant says, is something in which the a posteriori element of empiricism and the a priori element of rationalism are unified. The consciousness at the time of cognition should not be empirical or fragmentary, but there must be a pure consciousness underlying empirical consciousness, which has the power to unify. Kant called it “consciousness in general,” “pure apperception,” or “transcendental apperception.” As for the question of how the functions of sensation and understanding are connected, Kant said that imagination serves as the mediator between the two, as mentioned above.

Denial of Metaphysics and the Thing-in-itself

In this way, Kant discussed how certain knowledge is possible in the phenomenal world, namely, in the natural sciences or mathematics, and then examined whether or not metaphysics is possible. Since a metaphysical entity has no sense content, and therefore, can not become an object of perception, it can not be perceived. Since, however, the function of our reason is related to understanding alone and not directly to sensation, there are some cases in which one has an illusion whereby something that does not really exist appears to exist. Kant called this type of illusion “transcendental illusion.” The transcendental illusion consist of three types: the idea of the soul, the idea of the world, and the idea of God.

Among these, he called the idea of the world, namely, the cosmological illusion, the antinomy of pure reason. This means that when reason pursues the infinite being (the infinite world), it will reach two entirely opposite conclusions from the same basis of argument. An example of this is the two contradictory propositions: “the world has a beginning in time and is also limited in regard to space” (the thesis) and “the world has no beginning in time and no limits in space, but is infinite in respect to both time and space” (the antithesis). Kant held this to be an error derived from trying to grasp the sense content as the world itself.

Kant held that cognition takes place only to the extent that the sense content coming from the object is synthesized through the a priori forms of the subject, and that the object itself, namely, the “thing-in-itself,” can never be cognized. This is the agnosticism of Kant. The world of “things-in-themselves” is the reality lying behind phenomena, and is called the “noumenal reality.” Nevertheless, Kant did not totally deny the world of things in themselves. In his Critique of Practical Reason, he held that noumenal reality is to be postulated in order to establish morality. He also claimed that, in order for noumenal reality to exist, freedom, the immortality of soul, and the existence of God must be postulated.

3.2. Marxist Epistemology

Next, I will explain the epistemology that is based on the materialist dialectic. This is called Marxist epistemology, or the dialectical materialist theory of knowledge.

Theory of Reflection (Copy Theory)

According to the materialist dialectic, the spirit (consciousness) is a product or a function of the brain, and cognition takes place as objective reality is reflected (copied) onto consciousness. This theory is called the “theory of reflection” or “copy theory” (teoriya otrazhenia). Of this, Engels said, “we comprehended the concepts in our heads once more materialistically―as images [Abbilder] of real things.” Lenin stated that, “From Engels’ point of view, the only immutability is the reflection by the human mind (when there is a human mind) of an external world existing and developing independently of the mind.” In Marxist epistemology, what Kant called sense content is not the only reflection of the objective world upon consciousness. The forms of thought are also the reflection of the objective world; they are the reflection of the forms of existence.

Sensory Cognition, Rational Cognition, and Practice

Cognition is not merely a reflection of the objective world, but it has to be verified through practice, according to Marxist epistemology. Lenin explains this process as follows: “From living perception to abstract thought, and from this to practice,―such is the dialectical path of the cognition of truth, of the cognition of objective reality.” Mao Ze-dong explained the process of dialectical materialist cognition more concretely in the following quotes:

This dialectical-materialist theory of the process of development of knowledge, basing itself on practice and proceeding from the shallower to the deeper, was never worked out by anybody before the rise of Marxism…. Marxism-Leninism holds that each of the two stages in the process of cognition has its own characteristics, with knowledge manifesting itself as perceptual at the lower stage and logical at the higher stage, but that both are stages in an integrated process of cognition. The perceptual and the rational are qualitatively different, but are not divorced from each other; they are unified on the basis of practice.

The first step in the process of cognition is contact with the objects of the external world; this belongs to the stage of perception [sensory stage of cognition]. The second step is to synthesize the data of perception by arranging and reconstructing them; this belongs to the stage of conception, judgment and inference [rational stage of cognition].

In this way, cognition proceeds from sensory cognition to rational cognition (or logical cognition), and from rational cognition to practice. Now, cognition and practice are not something that take place only once. Mao Ze-dong said “Practice, knowledge, again practice, and again knowledge. This form repeats itself in endless cycles, and with each cycle the content of practice and knowledge rises to a higher level.”

Kant said that cognition takes place insofar as the subject synthesizes the object, and that it is impossible to cognize the “things-in-themselves” behind the phenomena, advocating agnosticism. In contrast, Marxism asserted that the essence of things can be known only through phenomena, and that things can be known fully through practice, thus rejecting Kant’s notion of “things-in-themselves.” About Kant, Engels said the following:

In Kant’s time, our knowledge of natural objects was indeed so fragmentary that he might well suspect, behind the little we knew about each of them, a mysterious “thing-in-itself.” But one after another these ungraspable things have been grasped, analyzed, and, what is more, reproduced by the giant progress of science; and what we can produce we certainly can not consider as unknowable.

Now, in the continuing process of cognition and practice, practice is held to be of greater importance. Mao Ze-dong said, “The dialectical-materialist theory of knowledge places practice in the primary position, holding that human knowledge can in no way be separated from practice.” Practice usually refers to human action on nature and social activities, but in Marxism, revolution is held to be the supreme form of practice among all kinds of practice. Therefore, it can be said that the ultimate purpose of cognition is revolution. In fact, Mao Ze-dong said, “The active function of knowledge manifests itself not only in the active leap from perceptual to rational knowledge, but―and this is more important―it must manifest itself in the leap from rational knowledge to revolutionary practice.”

Let us next consider the forms of thought in logical cognition (rational cognition). Logical cognition refers to such acts of thinking as judgment and inference, which are mediated by concepts, and in which the forms of thought play an important role. Marxism, which advocates copy theory, regards the forms of thought as the reflection of the processes in the objective world upon the consciousness, that is, as the reflection of existing forms. Among the categories (forms of existence, forms of thought) in Marxism, there are the following:





the finite and the infinite






the individual, particular, and universal

cause and effect

necessity and chance

possibility and reality

content and form

essence and appearance

Absolute Truth and Relative Truth

Knowledge, according to Marx, grows through the successive repetition of cognition and practice. That knowledge grows means that the content of knowledge is enriched, and that the accuracy of knowledge is enhanced. Therefore, the relativity and absoluteness of knowledge becomes an issue.

Marxism says that truth is what reflects objective reality correctly. It says that, “If our sensations, perceptions, notions, concepts and theories correspond to objective reality, if they reflect it faithfully, we say that they are true, while true statements, judgments or theories are called the truth.”

Furthermore, Marxism asserts that practice―ultimately revolutionary practice―is the standard of truth. In order to know whether or not cognition is true, all one needs to do is to compare it with reality and ascertain that cognition concurs with reality. Of this, Marx said, “Man must prove the truth, i.e., the reality and power, the this-worldliness of his thinking in practice,” and Mao Ze-dong said, “Man’s social practice [class struggle in particular] alone is the criterion of the truth of his knowledge of the external world.” In sum, revolutionary practice is the criterion of the truth of knowledge.

According to Marxism, knowledge in a particular period is partial, imperfect, and remains as only relative truth, but with the progress of science, knowledge approaches absolute truth to an infinite degree. Thus, Marxism affirms the existence of absolute truth. Concerning this, Lenin says, “There is no impassable boundary between relative and absolute truth.” Also, the elements which are absolutely true are contained within relative truths, and as they are accumulated steadily, they become absolute truth, according to Marxism.

This concludes my explanation about the traditional epistemologies. As mentioned earlier, I introduced, in summary form, certain traditional epistemologies for the reader’s reference.