Philosophical Methods

T. K. SeungDepartment of PhilosophyUniversity of Texas at Austin

What is the right way to do philosophy? You are unlikely to run into this type of question in mathematics, physics, or geology. But the methodological question has become important for us because we are no longer sure of what we are doing in philosophy. Unfortunately, I cannot show you the right philosophical method, but can outline four methods that have shaped the development of Western philosophy since ancient Greece: (1) poetic, (2) scientific, (3) dialectical, and (4) analytical. I will discuss these four methods chronologically.        Ancient Greek philosophy was born out of the Greek poetic tradition. The poetic texts of Homer and Hesiod were revered as the fountain of wisdom and as the staple for the education of Greek youth. In that regard, they played the same role that would be played by the Bible in Christendom. For almost two thousand years, most Christians have looked upon the Bible as the source of all wisdom and truth. For them, to be educated was to study and understand the words of God in the Holy Scripture. For example, Abraham Lincoln educated himself by reading the Bible. For the ancient Greeks, the poetic texts of Homer and Hesiod were the words of their gods and goddesses. They claimed to have gained their superhuman knowledge from their muses. Their knowledge was not only superhuman, but also comprehensive. Homer explained the events of the world in terms of the immortals, whose power controlled the fate of the mortals. He even displayed his knowledge of warfare in his account of the Trojan War and his understanding of human nature in his portrayal of warriors. But Hesiod did something so extraordinary that even Homer could not think of doing it. He explained the genesis of the immortals and their nature. This is what I mean by “the poetic method.” It is the poet’s way of explaining the mysteries of the world. Some early Greek philosophers imitated the poets by writing in verse. Especially Parmenides wrote his philosophical treatise as an epic and claimed to have been guided by a goddess of wisdom just the way Homer and Hesiod had been guided by their muses. He talks about two paths: the path to truth and the path to opinion. The first path leads to the knowledge of what really is; the second path leads to the opinion of what appears to be. He says that appearances do not really exist although they appear to exist. What really exists never changes, and all changes belong to appearances. He made all these points by arguments. This was his dialectical method.        Early Greek philosophy was soon dominated by the emergence of natural science, which started giving a better account of natural phenomena than the poets’ mythological account. The ancient quarrel between poetry and philosophy was thus shaped as the conflict between poetry and natural science. In Aristotle’s language, it was the conflict between mythologoi (mythological explanation) and physiologoi (physical explanation). The poetic method was to provide the poetic explanations of phenomena in terms of gods and their power; the scientific method was to formulate the scientific explanations of the same phenomena in terms of natural forces. These two types of explanation presupposed the startling distinction between reality and appearance (phenomenon). As Parmenides says, reality is what truly is; appearance is what only appears to be. This ontological distinction became the epistemic distinction between the explanans and the explanandum. Appearance was to be explained by reality. To provide such an explanation was to render an account (logos) of appearance. The poets used to do it in their

mythological or theological explanations; the natural scientists were now doing it in their physical or scientific explanations. Their most common examples were the attempts to explain physical objects in terms of basic elements such as earth and water, air and fire. Even more startling was the theory of Leucippus and Democritus that all appearances were made of invisible atoms in the void. The natural scientists repudiated mythological accounts as superstitions.        The wave of natural scientists was followed by the wave of Sophists. They were professional teachers, who dealt with the practical side of human life such as ethics and rhetoric, law and politics, whereas natural scientists were concerned with the theoretical questions. The word ‘Sophist’ meant a person of wisdom. The Sophists introduced adopted the dialectical method as their own. They were teaching how to use wisdom not in finding out truths, but in winning an argument in the courts of law and political assemblies. Hence they attracted a large group of students, who were aspiring to make careers in

law and politics. Their teaching became a big fashion in Athens just like논술 광풍 in Seoul. The most

illustrious Sophist Protagoras is said to have made more money as a teacher than the famous architect Phidias, who designed and supervised the construction of Parthenon. Another famous Sophist Gorgias was proud of comparing his power of persuasion with that of his brother. Although he knew nothing about the art of medicine, he used to brag, he could persuade patients to follow tough prescriptions much more effectively than his brother, who was a physician. Even Socrates was known as a Sophist. In fact, he was charged and tried for the treason of corrupting youth by his art of sophistry. What was remarkable about the method of Sophists was that it was completely based on the use of arguments. It was much more economical way than the method of poets or of scientists because it requires only the use of words. But it is not easy to prove anything by arguments alone. Without the support of reliable data, arguments appeared to be only rhetorical tricks. Hence tricky arguments came to be called sophistic arguments. Socrates was not a normal Sophist. He set out to counter the game of Sophists by using their own method. One by one, he tore apart their positions by arguments. He did not have to know anything beyond what his opponents were saying to show that their positions were self-contradictory. The logical principle of non-contradiction was sufficient for the task. Hence he was proud of saying that he knew nothing. His method was later to be called the method of dialectic or the dialectical method by Plato. Thus the third method of philosophy was born from Socrates and christened by Plato.         Plato transformed the art of Sophists into philosophy as his brain child. The word ‘philosophy’ meant the love of wisdom. His conception of wisdom was different from the Sophistic conception. Whereas the latter was the wisdom of winning arguments and persuading people, the former was the wisdom of knowing truth. Nevertheless, the dialectical method was fundamentally the same as Sophists’ method of argument although they were used for different purposes. Plato tried to demarcate philosophy as a new intellectual discipline not only from the art of sophistry, but also from natural science and poetry. In the Republic, Plato defended philosophy as the champion of truth and repudiates the authority of poetry on the ground that poets had no direct access to the ultimate reality. This was his replay of the ancient quarrel between poetry and philosophy. But that ancient quarrel had been originally fought against poetry by natural science. In his replay, natural science was replaced by Plato’s brain child, philosophy. But he does not want to identify his brain child with natural science. On the contrary, he recognized a new quarrel between philosophy and natural science in the Sophist, which he called the battle between the gods and the giants. The gods were philosophers; the giants were scientists. The latter espoused materialism; the former advocated idealism.        In the domain of truth and wisdom, Plato placed natural science higher than poetry, and philosophy even higher than natural science. In his view, natural science studies only phenomena, which are only the

sensible copies or appearances of supersensible Ideas. Hence natural science cannot deliver true knowledge, but only opinions. Poetry was even lower than natural science because the former deals not even with appearances, but with their semblances or copies of appearances.  In his day, geometry was the only well-established science. He admired it as a better science than natural science because the former deals not with sensible appearances but with supersensible truths. But he envisaged philosophy as a science even higher than geometry. Whereas geometry still has to employ hypotheses and sensible images in its search of supersensible truths, he hoped, philosophy should transcend the sensible world altogether because it deals with the nature of such supersensible Ideas as Justice and Goodness. Therefore philosophy should be the highest science. But what method is to be used by philosophy? He says that it is the method of dialectic. This method is not empirical like the scientific method, but a priori and transcendent. Hence he calls philosophy the dialectical science. He claims that the dialectical method is better than the poetic and the scientific method because it alone can grasp the nature of transcendent reality.         Plato, however, could not fully describe the nature of dialectical science because it was not yet an established science like mathematics, but only a future science that was being shaped in his own hand. He described it as the method of argument for understanding eternal Ideas. It is not hard to understand the use of arguments in the courts of law or political assemblies. But how can they be used for inquiring into the nature of supersensible reality? In Plato’s early dialogues, his Socrates uses critical arguments to expose the weakness of his opponent’s position. But this is the negative function of dialectic, which requires only the logical principle of non-contradiction. But how can the art of dialectic perform the positive function of finding the nature of supersensible reality? This was the most difficult question for Plato’s science of dialectic. But it was avoided in his early dialogues, which were limited to the negative function of dialectic. In his middle dialogues, Plato began to use the dialectical method for positive results. For example, he wants to prove the immortality of the soul in Phaedo. This was indeed a supersensible question, which cannot be settled by the evidence of the sensible world. But Plato cannot give a solid dialectical proof for the immortality of the soul. At best, he can give only a plausible account, which belongs to the poetic method rather than to the dialectical method. In fact, he has inherited the immortality of the soul as a poetic story from the Pythagoreans. He can embellish it, but cannot prove it. He does the same thing in the Republic. When his art of dialectic falls short of the philosophical task, he loves to employ the poetic method of parables and allegories. Those poetic stories and images have become famous, for example, the allegories of the sun and the cave, the analogy of travail. Thus Plato’s philosophy has turned out to be a heavy mixture of dialectical science and poetry. The dialectical method performs only the negative (critical) function of his philosophy, but its positive function is left for the poetic method.

        In Timaeus, Plato candidly admits that his poetic stories are only plausible (eikos) stories (그럴듯한

이야기). The story that the world is the body of the World-Soul is meant to be plausible in explaining the

teleology of the world. Plato struggled with this problem in Phaedo. If mind is the producer of order and the cause of everything as Anaxagoras says, it must arrange everything for the best. In the Republic, Plato tried to explain this universal teleology by postulating the Idea of the Good as the ultimate source of all things and arguing for the principle of optimality as the universal constraint on all rational behavior. But the Idea of the Good is not mind, and it takes mind to aspire for the Good. So he has decided to explain the principle of universal teleology by installing the World-Soul as the mind of the whole world. In Timaeus, even our mortal souls are said to be parts of this universal soul. The gods placed the immortal part of human soul in the head, whose spherical shape looks like heaven, and then segregated the head

from the rest of the body by placing the neck as an isthmus between them. The gods placed the two mortal parts of human soul in the chest. One mortal part is emotional; the other mortal part is appetitive. The gods placed the emotional part in the upper half of the chest, and the appetitive part in its lower half. In this mythological account, Plato brings together his tripartite theory of soul with physiology.         Plato’s mythological account was offered in the same spirit that the myths of Hesiod and Homer had been offered in their own days. In both cases, myths were meant to be not literally true, but only plausible. To be sure, Hesiod and Homer did not claim only the plausibility of their stories. On the contrary, they vouchsafed for their truth by the authority of their muses. This may be the difference of Plato from the poets. But their shared aim was to formulate plausible accounts. What appears plausible to one person may appear implausible to another because they have different knowledge and experience. What appears plausible to one age may appear implausible to another age because they do not share the same knowledge and experience. Homer’s and Hesiod’s stories had probably been as plausible for their age as Plato’s stories were for his age. Plato’s stories were based on the mental state of his age just as Homer’s and Hesiod’s stories had been based on the mental state of their age. Plausibility is a function of the currently available information and evidence. This point is beautifully illustrated by the six speeches on Love in the Symposium. The nature of Love is a big mystery for all the six speakers because none of them is fully acquainted with Love. But they have to weave plausible stories on the basis of their limited exposure to and experience of Love. Each of their stories is plausible in terms of his professional knowledge and experience. Even Socrates uses the dialectical method only in exposing the fallacy of Agathon’s uncritical praise of Love. But his recounting of Diotima’s story of love is only a plausible account of the mystery of Love. What was the motive for offering a plausible account? It was meant to be a substitute for a true account when a true story was not available. The poetic method is an attempt to reach out for what cannot be known by the scientific method. If the scientific method is defined as the method of demonstration, then the poetic method can be regarded as the method of plausible conjecture where there is no sufficient evidence or data for demonstration. The poetic method is the method of inquiry well short of the certitude of scientific knowledge.         Aristotle reshaped philosophy by using the scientific method. In his view, the dialectical method was too eristic to be trustworthy. Plato’s favorite science, mathematics, was not a real science because it dealt only with abstractions, not with full reality. Aristotle regarded the domain of nature as the only suitable object of philosophy. He constructed his philosophy as a system of natural science, which was divided into various special sciences such as physics, biology, psychology, meteorology, etc. His system of natural science included his poetics, rhetoric, ethics, and politics because they were scientific studies of the nature of humanity and its culture. Even logic was a branch of his natural science because it treated the universal laws governing all natural phenomena. For this reason, the Categories was the first of all his logical treatises. Many scholars have complained that this treatise was misplaced. In their view, it should have been treated as a metaphysical treatise rather than a logical one. In this treatise, Aristotle lays out the basic ontological categories for his ontology of nature and uses them in the remainder of his Organon as the basic premise for his systematic investigation of logical laws governing natural substances. His Metaphysics was never separated from his Physics, the general title for physical sciences. His Metaphysics does not treat any problems that transcend his Physics. On the contrary, the former treats the general problems that pervade the latter. But Aristotle left it without a title. So his editors coined a new word ‘metaphysics’ for its title by adding the prefix of meta to physics. The Greek word meta is equivalent to the English word ‘after’. The new title was meant to indicate not the substance of the work, but its sequence in Aristotle’s corpus, that is, Metaphysics comes after Physics. From physics to

metaphysics, from logic to ethics, Aristotle used the scientific method for his science of substance and its essences. But it failed at the most critical point of his scientific enterprise. He had inherited the principle of teleology from Plato and tried to account for it by his theory of prime movers. But there was no scientific evidence for this theory. Hence it was no more than a plausible account of natural teleology. Nevertheless, Aristotle succeeded in transforming most of philosophy into natural science.        Medieval Christianity presented a wonderful stage for Platonism because it stressed the supersensible world, the object of Christian faith. Plato’s dialectical method was especially useful for Christian theology because the object of its discourse, God, transcends the phenomenal world. St. Augustine used the dialectical method for proving the existence of God. But he had one serious problem with this method. Although the principle of non-contradiction was the basic principle of dialectical arguments, he found himself running into contradictions in his discourse about God. The doctrine of Trinity was an outright contradiction. It was contradictory to say that God was one and three at the same time or that Jesus Christ was the son of God and God at the same time. The omnipotence and omniscience of God was contradictory with the freedom of His creatures. The idea that Jesus was divine and human at the same time was also contradictory. As God, he would have known that he would be betrayed by Judas. But he could not have known it as a human being because no human being is omniscient. In his dual nature, Augustine had to say, Jesus knew and did not know at the same time about the impending betrayal by Judas. If Augustine were faithful to the dialectical method, he should reject the entire Christian theology. But he did the opposite. He did his best in saving Christian theology even by suspending the principle of non-contradiction. When the dialectical method failed him, he just appealed to the authority of the Bible, the poetic story of God and His creation. But the biblical stories could not be taken literally. So he had to interpret them allegorically, thereby promoting the allegorical sensibility for Christian theology. Thus, the allegorical method developed as a special form of the poetic method of understanding God and the mystery of faith. The allegorical method had one special advantage for theology. It can easily avoid contradictions because the principle of non-contradiction directly applies only to literal expositions, but not to allegorical expositions. Hence it became the favorite method for all theologians.            The allegorical method in Christian theology was reinforced by the emergence of Christian Neoplatonism. The theology of John Scotus Erigena was highly poetic and allegorical; his description of the world as the Tree of Life growing out of the fountain of God became an enduring legacy for Christian theology down to St. Bonaventure of the thirteenth century. St. Bernard of Clairvaux of the twelfth century was a Neoplatonic theologian, whose Steps of Humility was a allegorical discourse on the way to God. This treatise became a model for later theologians, especially St. Bonaventure and his treatise, The Journey of the Mind to God. St. Bernard often used the Song of Solomon for his sermons on the love of God. Eighty-six of those sermons have survived, and all of them abundantly display his poetic conception of God. The allegorical method finally came to its full fruition with Dante. George Santayana calls him a philosophical poet along with Lucretius. But a philosophical poet is different from a poetic philosopher. Lucretius was indeed a philosophical poet, but Dante was a poetic philosopher. Lucretius presents the Epicurean view of the world in his poetic language. But Dante does not merely present medieval Christian theology in his poetic language. As I have shown in my Fragile Leaves of the Sibyl, his Divina Commedia presents a far more systematic understanding of the Holy Trinity than that of St. Augustine or any other medieval theologians. But this point has never been noted in Dante scholarship because his method of exposition is not literal but allegorical. In his epic journey, Dante sees only human beings except for two occasions. He sees Satan at the bottom of Hell and God at the top of Heaven. Between these two points, his epic vision is a grand panorama of humanity. Hence his epic has been read as a

Human Comedy rather than as a Divine Comedy. This interpretation has been justified on the supposition that Dante’s epic celebrates the newly emergent secular ethos of the Renaissance rather than the medieval religious ethos. Many scholars have supported this supposition by the fact that Dante’s epic was written in the vernacular Italian, the language of Renaissance secular culture. But I have shown that every scene in his epic is an allegorical representation of the Holy Trinity, that is, their cosmic operation in the redemption of humanity. His conception of the Trinity is even more original than that of Augustine and Aquinas. That makes Dante a great poetic philosopher in his own right. Medieval Christianity produced a greater glory for the poetic method than any other period of Western philosophy.        In medieval Christianity, the dialectical method had its own bloom when St. Anselm invented his ontological proof for the existence of God in the twelfth century. This proof is purely dialectical. Instead of rejecting the principle of non-contradiction, he uses it as the only principle for his argument. This was the beginning of medieval scholasticism, which was further developed by the later scholastics in the thirteenth and fourteenth centuries. When Aristotle was introduced to the Latin West, his philosophy was inseparable from natural science. The medieval theologians separated metaphysics from physics and redefined metaphysics as the science of God because it transcended the physical world. Their theology became metaphysics, but their physics still belonged to philosophy. It was also called natural philosophy even down to the time of Newton, who regarded his physics as natural philosophy, as indicated by the title of his masterpiece, Principia Mathematica Philosophiae Naturalis. Although natural science had been treated as a junior partner of traditional philosophy, it started making astounding progress with Galileo’s invention of mathematical physics, which was markedly different from Aristotelian physics. Natural science began to establish itself as a fully independent science, while traditional philosophy was still fumbling and groping in the dark. Traditional philosophy faced the imminent danger of being overpowered and even swallowed up by natural science. This was the crisis of philosophy that greeted Descartes. He could not save the integrity and independence of philosophy without demarcating the province of philosophy from that of natural science. This territorial demarcation was the Cartesian revolution for modern philosophy, but it was a revival of Platonic conception of philosophy as a transcendent science against the Aristotelian tradition.         The Cartesian revolution began with Cartesian doubt, which was rooted in the representational theory of perception. Our commonsense view of perception is direct (or naïve) realism, that is, we directly perceive physical objects. Confidence in this commonsense view was forever shattered by Cartesian doubt. Descartes holds that perception can never be in direct contact with physical objects because it is nothing but sensation. Our sensation is always subjective and belongs to what Descartes calls objective reality, the domain of subjective ideas and sensations. On the other hand, physical objects belong to formal reality, which is inaccessible to our perception. There is an unbridgeable chasm between the domain of subjective sensations and the domain of objective reality. To prove this point, Descartes challenged his readers to distinguish their dreams from real perceptions. It has been a big scandal in philosophy that no one has been able to meet this simple challenge. There is no way for you to be sure that your present experience is not a dream.         The basic point of Cartesian doubt is that there is no way to find out the exact relation between our perceptions and the physical world. At most, we can say that our perception represents physical objects. But there is no way to know what they are like in themselves. If this is the upshot of Cartesian doubt, it can undermine the foundation of natural science because scientific investigations are based on the naïve confidence that the physical world is directly accessible to our perception. If Descartes is right, the foundation of physics is not the physical world, but our perceptual world. If the latter is doubtful or

illusory, natural science should be equally doubtful or illusory. This is the question of foundation for natural science. But it cannot be handled by natural science, according to Descartes, because it is not an empirical question. He takes it as a philosophical question par excellence because it transcends the empirical domain. Philosophy must be an a priori science because its function is to provide the a priori foundation of natural science. This is his new conception of philosophy, which is labeled as “First Philosophy” in his Meditations on First Philosophy. Cartesian First Philosophy can be called metaphysics because it transcends or goes beyond physics. But its transcendent object is the physical world. Because it lies beyond our perception, it is as transcendent as God or Platonic Ideas. The physical world was never regarded as transcendent by ancient Greeks or medieval Christians. This is the novelty of Cartesian philosophical perspective. The natural world has suddenly become transcendent and inaccessible for the mortals.        What method is Descartes going to use in providing the a priori foundation for natural science? It cannot be the scientific method because it is meant to go beyond or rather below natural science. The Cartesian method is to use innate ideas. Since these ideas are not empirical, he regards them as the suitable media for providing the a priori foundation for natural science. He claims that innate ideas must be true because they are clear and distinct. But he concedes that he can be mistaken even about clear and distinct ideas if he is manipulated by an evil demon. So he has to prove that there is no such demon. To this end, he tries to prove the existence of God. His first premise for this proof is the innate idea of God as the most perfect being or the infinite being. As a finite being, he says, he cannot be the author of the innate idea of an infinite being. Therefore, his innate idea of God must have come from God himself. This is his proof for the existence of God. He then proves that God cannot be a deceiver because God is the most perfect being. Nor can God allow an evil demon to deceive human beings. This can justify our belief in the truth of clear and distinct ideas. From this he moves on to the proposition that mathematics must be true because it is composed of clear and distinct ideas. With this validation of mathematics, Descartes holds that mathematics can serve as the foundation of natural science.         This is a rough outline of Cartesian dialectic of innate ideas, which contains all the evils of eristic argument. First of all, Descartes has no ground to make the distinction between innate and empirical ideas because this distinction presupposes the demarcation between himself and his external world. But he has no contact with the external world and is not even sure of its existence. Second, contrary to his contention, there is no way to prove that the idea of God is innate, or that this idea is clear and distinct. In fact, it is one of the most obscure ideas. Finally, although he can apply mathematics to the perceptual world, he has no way of knowing whether he can apply it to the physical world because he has no access to it. Hence mathematics cannot serve as the scientific foundation for studying the physical world. Thus Cartesian dialectical arguments turn out to be a web of sophistry. But the same type of metaphysical arguments was perpetuated by Malebranche, Leibniz, and other followers of Descartes. Kant exposed their sophistry in his Critique of Pure Reason. Their dialectics are solely based on concepts, which are devoid of objects. Without objects, all metaphysical speculations are empty and illusory. This is his systematic critique of the dialectical method and dialectical metaphysics.        Kant, however, did not abandon the Cartesian project of securing the foundation for natural science. On the contrary, he expanded it because he believed that a priori foundations are needed not only for natural science, but even for mathematics. To provide such foundations was his transcendental project. The basis of this project is the science of logic because it is the only science of pure reason. But Kant believes that logic can produce no knowledge because pure understanding has no object. He also believes that objects can be gained only through intuition and that there are two kinds of intuition, pure and

empirical. Space and time are pure intuitions; all sensations are empirical intuitions. By the union of pure intuitions with pure understanding, Kant claims to transform empty formal logic into transcendental logic that can generate a set of synthetic a priori propositions such as mathematical axioms and the universal causal principle. These a priori synthetic propositions will provide the a priori foundations for mathematics and physics. This is the outline of his transcendental philosophy. Its method is not dialectical but scientific. Most important of all, it is an a priori scientific method whereas natural science employs an empirical scientific method. Therefore, philosophy is a super-science.        There were a couple of serious problems with Kant’s super-science. First, he claimed to derive all pure concepts of understanding by logic alone, but his derivation of those concepts was a systematic trickery. His transcendental logic was based on this logical sleight of hand. Second, even if his transcendental logic were to provide the a priori foundation for natural science, it could not do the same for moral and political philosophy. In short, its scope was too narrow. For the remedy of this defect, Hegel replaced Kant’s transcendental logic with his dialectical logic, through which he claimed to derive the entire world of Absolute Spirit in a long chain of logical deduction. He freed his dialectical logic from the constraints of pure intuitions, which had restricted the domain of Kant’s transcendental logic to mathematics and physics. Thus freed from the chain of intuitions, his dialectical logic gained the autonomy of working out its own development from the concept of Pure Being to the realization of Absolute Spirit, which was divided into three stages, Logic, Nature, and Spirit. In the first stage, Hegel used his dialectical logic for deducing the entire logical system of concepts and ideas. In the second stage, he deduced the entire system of nature from the mechanical and chemical to the biological level. In the third stage, he deduced all the components of the cultural world—economics, politics, laws, morals, arts, religion, and philosophy. But there were too many gaps in the Hegelian chain of logical deduction. All these wonderful things could not have been deduced from logic, whether dialectical or transcendental, without eristic trickery. Logic is the thinnest of all sciences. Its expansion in content can be made only through theft and deception.        Even after Kant’s transcendental logic and Hegel’s dialectical logic had been discredited, the idea of philosophy as an a priori science never died. But the Kantian ambition of reformulating philosophy as a system of a priori synthetic propositions was forever abandoned. Since it was impossible to have a priori synthetic truths, philosophy had to settle for the modest goal of a priori analytic truths. This was the birth of analytic philosophy. Its method of analysis can be divided into two types: logical analysis and conceptual analysis. The logical analysis is to analyze the logical structure of a sentence, whose surface grammar can be misleading. Consider the sentence “Unicorns do not exist.” Its subject is “unicorns”; its predicate is “do not exist.” The sentence seems to say that unicorns do not have the property of non-existence, which implies that there are unicorns. They must exist if they have any properties. On the basis of this logical argument, some philosophers claimed the existence of unicorns in some form or other. But this metaphysical claim arises from confusing the grammatical subject for the real subject. The sentence “Unicorns do not exist” talks not about unicorns, but about the concept of unicorns. It says that there is nothing that can be subsumed under this concept. Therefore, a correct logical analysis of this sentence should translate it to “There is nothing that can be called a unicorn.” This shows that the real subject of this sentence is not unicorns. Lewis Carroll makes fun of the confusion between the grammatical and logical subjects in Through the Looking Glass. Consider the two sentences, “Achilles was the fastest runner. Nobody could run faster than he.” They seem to contradict each other. The second sentence seems to say that there was someone called Nobody who could run faster than Achilles. If so, Achilles could not have been the fastest runner. But “Nobody” is not the real subject, but only the grammatical subject of the

sentence. Suppose that you tell your friend, “Nobody can understand your problem because it is so complicated.” If your friend mistakes the grammatical subject for the real subject, he will beg you to help him find that rare person called Nobody. To understand the difference between grammatical and real subjects is to know how language operates. And it requires no empirical research because it can be done by logical analysis. Therefore it can belong to philosophy as an a priori science.         Conceptual analysis is the analysis of a concept or the meaning of a word or sentence. It is reminiscent of Socrates’s questions such as “What is justice?” or “What is reality?” Hence some have said that conceptual analysis is a revival of Socratic game of definition. But a Socratic question can be stated in two different forms. “What is reality?” may mean “What is the nature of reality?” or “What is the meaning of the word ‘reality’?” “What is the nature of reality?” cannot be answered without investigating the nature of reality. But “What is the meaning of the word ‘reality’?” can be answered by simply analyzing the concept of reality. The latter question is analytic; the former question is synthetic. After Kant, philosophy as an a priori science has been known to be unfit for handing synthetic questions. But it can still handle analytic questions. Hence conceptual analysis can belong to philosophy as well as logical analysis. Philosophy has become the science of analytic truths.                The laws of logic have served as the foundation for analytic truths. But this foundation was attacked by Quine around the middle of the last century. He rejected the distinction between analytic and synthetic propositions. He argued that the distinction in question was only a philosophical dogma and that all propositions were synthetic except for tautologies. Even the meaning of a word was not analytic. Quine said that there was no difference between a dictionary and an encyclopedia although one was assumed to be a book of meanings and the other a book of knowledge. Since there are no analytic truths, Quine declares, there can be no a priori science of even analytic propositions. He makes no exception even for logic. He denies a clear demarcation between logic and other sciences. No doubt, logic deals with the most general propositions, but all of them have to be justified empirically. Logic can be more general than other sciences, but it cannot be any less empirical than the latter. If all propositions are empirical, the Cartesian idea of philosophy as an a priori science is only a phantom. Quine argues that it is about time to free ourselves from the pursuit of this phantom and naturalize philosophy. This is to pursue philosophy in the same empirical manner as we pursue natural science, that is, by the empirical method. For example, epistemology, which has been the heart of modern philosophy since Descartes, should become a chapter in empirical psychology. Because Quine was a behaviorist, he tried to naturalize the philosophy of mind by behavioral psychology. But neuroscience is a much better way of naturalizing the philosophy of mind. Behavioral psychology, which is limited to the relation between inputs and outputs, does not investigate how inputs are processed into outputs. This neural processor can be provided by neuroscience. Behavioral psychology can give only a quasi-naturalization of philosophy, which can be fully naturalized by neuroscience.         Let us consider the prospect of naturalizing the various branches of philosophy The first obvious target is semantics, the science of meaning. Although field linguistics is an empirical science, some philosophers may say, the science of meaning cannot be empirical because meanings are intentional entities. But Quine handles the question of meaning as the question of stimulus and response, whose neural processing can be better studied by neuroscience. Syntax can also be naturalized if the basic forms of syntax are engraved in our brain as Noam Chomsky says. The naturalization of logic should follow that of syntax because its basic principles must also be located in our brains. The philosophy of mathematics can be also studied by neuroscience. If mathematical concepts are a priori, they must also be located in our brains. A central question of ethics is whether the sense of right and wrong is a priori or a posteriori

or whether conscience is innate or acquired through acculturation. Although it has been impossible to settle this question philosophically, it can be settled by the development of neuroscience. Even those, who refuse to recognize any a priori elements in our moral experience and take moral judgment as the expression of emotion, can use neuroscience for the confirmation of their theory. The function of emotion should be a function of the brain. This will be the naturalization of ethics. The naturalization of ethics should pave the way for the naturalization of aesthetics because aesthetic sensitivity belongs to the domain of feelings whether those feeling are a priori or acquired. Even the old metaphysical question of free will can be decided by neuroscience. If the human brain is governed by deterministic laws, then it has no freedom. If it is not, then it has free will. Some people may regard it as a misconception of free will to equate it with its indeterminacy. But free will is none other than the power of making choices in the world of indeterminacy. Therefore, even dogs and frogs can have free will, if their brains are not governed by deterministic laws. There may be other definitions of free will. No matter what the definition you may have, as long as it is phrased in neural terms, then you can decide the question by natural science. But I do not mean to say that the naturalization of philosophy should be limited to neuroscience. It can also use other natural sciences such as evolutionary biology, cultural anthropology, and genetics. These disciplines have recently produced extensive studies of innate dispositions in the human mind. When all philosophical problems are naturalized, they will become scientific problems that can be decided empirically. With the dissolution of philosophical problems, philosophy will be dissolved into natural science.         The naturalization of philosophy appears to leave no more philosophical problems in their old form. But some philosophers may say that there are quite a few metaphysical problems still untouched by the Quinian naturalization, for example, the old mind-body problem, whether mind and body are identical or different, or whether mental phenomena are reducible to physical phenomena. These questions can be decided by philosophy, not by neuroscience, according to some philosophers. But, in fact, neuroscience has not advanced far enough to decide these questions. Hence all discussions on the reducibility of mental to physical phenomena are scientifically groundless. The only thing that neuroscience can assure us is the correlation between the mental and the physical, that is, there can be no mental phenomena without physical bases. But philosophers do not have any special intuition to the mind-body relation that neuroscientists do not have. At most, philosophers can make logical distinctions such as property dualism vs. substance dualism, strong vs. weak supervenience, and global vs. local supervenience. But these distinctions are just logical matters of definition; they are not offered as scientific theories. Hence they can make no difference for the naturalization of philosophy because they are insignificant and irrelevant for neuroscience.         Kant aspired to reshape philosophy as a science of a priori synthetic truths, but Quine has shown that the only way to make philosophy into a science is to transform it into a natural science. In the twentieth century, Western philosophy was driven by the obsessive ideal of becoming a solid science. Hans Reichenbach called it the rise of scientific philosophy. Natural science as the model for philosophy was not restricted to analytical philosophy. The phenomenology of Husserl, Heidegger, and Sartre was also conceived as the science of phenomena. But it has generated the anti-scientific movement called deconstruction and terminated continental philosophy as an intellectual discipline.The naturalization of philosophy will also bring about the end of philosophy because it will transform it into a natural science. Let us review the various methods that have been used for the pursuit of philosophy, (1) the poetic method, (2) the scientific method, (3) the dialectical method. The last of these three has been least reliable. The scientific method has been most popular. But it has been used for

producing four different types of science: (a) the Aristotelian science of essences, (b) Kant’s science of a priori synthetic truths, (c) the post-Kantian science of analytic truths, and (d) Quine’s science of naturalized philosophy. But what has happened to the poetic method in the Cartesian tradition? Has it been completely forgotten? No, Kant himself used it. He was obsessed with the scientific method in the first Critique because he was driven by his ambition to establish metaphysics as a solid science. But he could not use the scientific method for formulating his moral philosophy because he was convinced that “What ought to be” could not be derived from “What is.” Briefly in his Groundwork for the Metaphysics of Morals, he advanced the thesis that all moral rules could be derived from the simple logical principle of formal consistency. That was a highly implausible view because the requirement of formal consistency is too weak to discriminate moral from immoral rules. In fact, as Hegel says, even immoral rules can meet this minimal requirement. In the Critique of Practical Reason and the Metaphysics of Morals, Kant abandoned this simple moral theory and embraced Platonic Ideas as the ultimate principle for morals and laws. We can make no sense of moral experience without appealing to those eternal Ideas. But there is no way to prove their existence. Therefore, their existence is only our necessary postulate for morality. A postulate is a plausible story, a poetic fable. This is Kant’s poetic method. He ran into the same problem in accounting for our experience of beauty and again appealed to Platonic Ideas. So his philosophy of morality and aesthetic relied on the poetic method just as Plato’s philosophy had.        The poetic method was best exemplified by Goethe. He was a poet deeply inspired by Kant’s aesthetics and also a scientist well versed in biology. He had his own idea of biological evolution many years before Charles Darwin. In the opening of his Origin of Species, Darwin duly acknowledges Goethe as one of his precursors. But Goethe did not have the good fortune of gathering the sort of biological evidence that became available to Darwin. Because Goethe could not give his idea of evolution a scientific proof, he presented it in his epic poem, Faust. It is presented in the Classical Walpurgis Night of Act 2, Part II of Faust. It portrays the emergence of living beings in a dark cave at the bottom of the Aegean Sea. This cave is the temple of life; it is the shrine to the Primal Darkness. When Mephisto goes down there, he finds three Phorkyards, who share only one eye and one tooth. They are formless and ugly. The Aegean journey of Faust and Mephisto displays the evolution of beautiful forms of life from formless matter and its chaotic energy until it produces the beauty of Galatea and Helen of Troy together with the beauty of the sun and the moon. By using the poetic method, Goethe is trying to go beyond the frontier of the science of his own day. This is his attempt to have a poetic glimpse of what is not accessible to the solid scientific method. Even Hegel’s dialectical logic can be tolerated if it is taken not as a massive logical trickery, but as a poetic vision to see the world as a Neoplatonic emanation. Schopenhauer was also poetic in portraying the world as a theater of perpetual suffering. His poetic inspiration came not from science, but from Hinduism. Kierkegaard derived his inspiration from Christianity in becoming a poetic philosopher of faith. He says that he is a poet talking about the mystery of religious faith. Nietzsche was also highly poetic. His greatest work, Thus Spoke Zarathustra, has long been regarded as a philosophical treatise. Although it contains a long series of philosophical aphorisms, it has been impossible to read it as a philosophical treatise because those aphorisms harbor a series of logical contradictions. So I have proposed to read the whole work as an epic, that is, Zarathustra’s epic journey in search of his destiny as a sovereign individual in a deterministic world. The conflict of a sovereign individual with his deterministic world underlies all the previously noted contradictions in this work. Thus I have resolved all those contradictions and revealed the sense of majesty and triumph that sustains Zarathustra’s epic journey as Greg Whitlock has said in praise of my interpretation.            None of these poetic philosophers are competing against natural science. Nietzsche was well versed

in physics of his day and fully accepted its determinism. Goethe’s knowledge and appreciation of natural science was equally outstanding. But they did not believe that natural science had fathomed the mystery of nature. So they were trying to reach out for the mystery of reality beyond scientific understanding. This is the motive for their poetic visions. This was also the case with Dante. He was fully acquainted with the natural science of his age, but his intellect could not be contained within scientific confines. He could have said, “I cannot live with science alone any more than I can live with bread alone.” In search of his spiritual bread, he carved out his poetic vision of the universe in the Divina Commedia. His poetic vision was not meant to go against natural science. On the contrary, it was built on the available scientific knowledge. But his poetic method was his way of transcending the scientific method. This is exactly the way Plato used the poetic method for transcending the limits of natural science. The poetic method is liable to be misunderstood as the method of fiction, that is, the licentious method of making up groundless stories. Fiction as an important genre of literature has been an invention of modern Europe. In ancient Greek, poetry had nothing to do with fiction. Homeric epics were meant to be stories of real historical events. Aristotle says that poetry is more philosophical than history. This is his way of saying that great poetic stories reveal the spirit of an age more deeply than factually accurate historical accounts. Hence the poetic method can be developed by only those with a comprehensive understanding of the scientific worldview. This is why there have been so few poetic philosophers in the world. It is not easy to gain a comprehensive scientific view of the world. It is even rarer to be born with a great poetic talent. But to wed poetic talent with scientific understanding is more difficult to achieve than any other form of union.        The poetic method is almost dead in contemporary philosophy because it has been smothered by the envy of science. The scientific philosophers have derided poetic philosophy by saying that it is not philosophy but only poetry. But the poetic philosophers can return the compliment and say that scientific philosophy is not really philosophy but only a poor imitation of science. If Quine is right, their imitation of science can become truly scientific only if their philosophy is transformed into a natural science. But most philosophers do not have the scientific competence to make the transformation. So they had better stay with the analytic method and defend the fortress of analytic truths against Quine’s vicious assault. But there is one saving grace for the analytic method. It is the cheapest and easiest method to learn because it can be sustained by the logical principle of non-contradiction alone. For the sake of respectability, we may reclassify it as a dialectical method because it is not empirical. But it is a dialectical method without transcendence. Hence it harbors little danger of metaphysical trickery, but cannot avoid the boredom of trivial analysis such as a bachelor as an unmarried male. It can never generate intellectual excitement and enlightenment in doing philosophy. Nor can it make any significant contribution to the liberal education of our youth. For these reasons, we had better seriously consider the revival of the poetic method in philosophy.