Thomas Kuhn argued that the history of science could be understood as progressing between periods of “normal science” and “revolutionary science.” Periods of “normal science,” during which observations fit within a general theory, are interrupted by periods of revolutionary science when enough anomalies occur to justify the creation of a new theory. In this paper I will argue that Kuhn’s dichotomy can be applied to the history of philosophy as a whole. Philosophy has cycled between periods of “normal metaphysics” and “revolutionary metaphysics.” The revolutions in metaphysics came about as a result of many complete revisions of metaphysical systems, resulting from the skeptical arguments of key philosophers throughout history.
The first period of normal metaphysics began with Plato’s theory of the forms, and ended with Descartes’ demon questioning all knowledge. Descartes began the second normal metaphysics by dividing soul from the world, and stressing the importance of the a priori. Hume’s skeptical indictment of induction created the next metaphysical crisis, which was then answered by Kant’s totalizing metaphysics. Kant’s new normal metaphysics evolved over time until Nietzsche declared “God is dead,” attacking the implicit assumptions of Plato, Descartes, and Kant—the three fathers of various normal metaphysics. But, as Heidegger points out, even Nietzsche created a new metaphysics within his concepts of eternal recurrence and the Übermensch. I will explore the grand succession of metaphysical inquiry under the framework provided by the Kuhnian progression of science: periods of normal metaphysics are abruptly ended by powerful skeptical arguments, until a new, revolutionary form of metaphysics evades each skeptical argument and is normalized until the next revolution.
Part 1: Axial Metaphysics
Plato’s worldview, an example of the axial model of thought, exemplifies the first period of “normal metaphysics.” The axial model is best understood as the belief that the world of appearances is deceitful, but that there exists a greater world of true reality. The axial purpose of life is to move from a fully contingent understanding of the universe, to an account that is timeless and eternal. Many of Plato’s philosophical forefathers emphasized the importance of finding systematization, form, and unity in the illusory experience of mankind. Born roughly a century before Plato, Parmenides described the world of appearances as false and deceitful. Parmenides has been recognized as one of the earliest proponents of a strong distinction between appearance and reality. Plato, having synthesized this distinction, expanded upon it in his own works. Plato argued that only through dialectical inquiry is it possible to transition from mere contingency into knowledge of the unchanging.
Axial metaphysics dominated philosophical thought for an enormous stretch of history. The hope to get beyond mere appearances and contingency, into the realm of true reality has served as the primary assumption for this first period of normal metaphysics. This assumption has been utilized by Plato’s theory of the forms as well as by Aristotle’s teleological view of nature. Other philosophers, like Saint Augustine, have used this assumption to explore religion.
Saint Augustine’s philosophy can be categorized as a combination of the assumptions of the axial metaphysics and Christianity. Saint Augustine’s personal beliefs towards religion also happened to expand upon the assumptions of Platonism. Saint Augustine utilized Plato’s conception of the form of the good, to justify religion. Plato conceived the form of the good to be something from beyond which is the source of the very existence of the forms. Augustine’s philosophy can be understood as replacing Plato’s conception of “the good” with God and of “the forms” with the divine. The axial divide between appearances and reality can also be observed in Augustine’s division between the City of Man and the City of God.
Kuhn explained that during periods of normal science, primary assumptions are not examined. Rather, the purpose of exploration is to rationalize and support intuitions. Similarly, Nietzsche explained, “Every great philosophy so far has been…the personal confession of its author and a kind of involuntary and unconscious memoir” (13). It can be seen in works like Confessions that Augustine was tormented in his search for a philosophy that unified his religious beliefs, actions, and philosophy. Augustine’s worldly, instinctual drives plagued him. He sought a serene, other world. The axial assumptions served as a marvelous stage on which Augustine built his City of God. Augustine utilized the power of philosophical discourse to ground his religious convictions. His axial foundations granted him the ability to cut through the layers of contingency in order to reveal the true nature of the universe—the nature of God.
Part 2: Cartesian Metaphysics
Unlike Augustine, René Descartes was not satisfied with building upon the edifice of Platonism. Beginning in the 16th century, a scientific revolution—powered by human rationality—began to bring order to the universe. The scientific revolution sparked a significant skeptical problem for Descartes. He found numerous uncertainties in the Platonic tradition. As a result, Descartes believed that knowledge needed a new basis. Descartes felt it necessary to raise questions of radical skepticism, in order to purge his mind of unjustified beliefs. This realization was pivotally important for philosophy, because it represented a complete revision of the cornerstone of the old, axial metaphysics. As Kuhn pointed out, once a large number of anomalies build up, science entered a stage of “revolutionary science.” Descartes believed that philosophy needed to take an entirely revolutionary approach. Despite his background in science and mathematics, Descartes skeptical questioning prompted a fervent revolution in metaphysics and philosophical inquiry as a whole.
When Descartes decreed his famous maxim “cogito ergo sum,” he created the new foundations for any future metaphysical undertaking. Descartes’ philosophical mission was to find a way around all methodological doubt. He questioned all sources of knowledge that lacked infallibility. For Descartes, the most infallible source was the senses. Uncertainty was the skeptical crisis that fueled Descartes revolution. Not only are the senses often explicitly inventive—like during a mirage—but the senses could be tricked by an all-powerful demon, and we would have no way to tell. This undermined Platonic metaphysics. If the world is a fictitious lie, then the forms must be false as well. Descartes found certainty in his own ability to think. For as long as he could think, he must necessarily exist. Descartes’ solution to his skeptical problem used the cogito in order to prove the existence of God, which in turn guaranteed the validity of the rest of human knowledge.
Descartes found a way to overcome an all-powerful demon, but in the process, he divided the world in two. Methodological doubt forced Descartes to disregard any knowledge gained through perception alone, leaving Descartes to trust only his inward thoughts. Therefore, Descartes was left with a dualist perspective of the mind and body. This perspective revolutionized both philosophical discussion and metaphysical discourse. Descartes didn’t eliminate the use of the axial model, for he too questioned appearance and desired reality. Rather, he reoriented the focus of metaphysics from the Platonic distinction between appearance and reality to the distinction between the mind and body.
Part 3: Kant’s “Copernican Revolution”, Transcendental Idealism
Hume reacted strongly against Descartes’ rationalist tradition and prompted the next philosophical crisis by tackling the twin monoliths of Cartesian metaphysics: reason and the transcendental ego. Hume questioned the powers of reason and denied that there was a certain self capable of finding important truths in a priori statements. Hume’s skeptical questioning of inductive reasoning in turn inspired Kant to undertake the most fundamental revision thus far: an attempt to discover foundations for all metaphysical beliefs.
According to Hume, Descartes’ mistake was putting such complete faith in the powers of reason. Hume’s first skeptical argument placed limitations on the powers of inductive reasoning—the ability to make future claims about past patterns. Hume argued that induction couldn’t be supported by logic, because the patterns we observe fail to rule out the possibility that something different will occur in the future. His second skeptical argument is that the self is “nothing but a bundle of perceptions.” Hume’s conception of human psychology was that the being never comes into contact with his or her own self, but rather only with the chain of sensory experiences. There is no ego we can locate in humans. Thus, any attempt to derive a priori knowledge cannot produce a proof of God’s actual existence. Similarly, if we deny the transcendental ego, all Cartesian arguments about God, the self, causation, and logical necessity would have to be swept aside.
As Descartes’ dominoes began to fall, Kant rose to Hume’s skeptical challenge to prove that reason does in fact possess great strength. Kant brought about the next period of normal metaphysics through the most coherent and totalizing metaphysical revolution of all. Kant’s project was to synthesize the empiricist and rationalist tradition by arguing for the existence of synthetic a priori statements. He sought to provide a compelling solution to Hume’s problem of the self and induction. His view was that the brain imposes structures upon the marvelous flux of incoming sensory input before the conscious being is even aware of the data’s existence.
Kant’s ‘Copernican Revolution’ solved the problem of the transcendental ego and causation by showing how the self and causation are both principles that the mind always and necessarily imposes onto experience. Kant explained the possibility of the synthetic a priori by means of mental necessity. A priori judgments can apply to our conception of facts in the world if the mind imposes categories on the world before we are allowed any access. Kant argues that before the mind perceives anything, the brain has already imposed categories of time and space. Kant’s solution to Hume’s problem is that our brain imposes various concepts into our perceptions before we become aware of them—making our very experience dependent on these transcendent properties. Kant’s new normal metaphysics escapes Hume’s objections by grounding cause and effect in synthetic a priori judgments. Under Kant’s newly constructed assumptions for any metaphysical judgments, Hume’s empiricist objections hold no weight.
Kant denied the entire prospect of axial metaphysics by replacing the axial project with the new metaphysics of German Idealism. Kant recognizes that it is impossible for us to understanding the noumena—the reality—the way things are “in themselves.” Transcendental Idealists believe that properties found in objects are dependent on the way those objects appear to the subjective, perceiving subject. Essentially, perceptions make up the appearances— the phenomena. Though Kant never doubted that noumena exists, he believed that we can never know its nature. We can only know the nature of phenomena. The Kantian revolution in metaphysics silences the axial model. Kant’s argues that absolutely impossible to travel beyond the phenomenal into the noumenal—it is impossible to move from appearance to reality.
Part 4: “God is Dead”
The final metaphysical revolution was Nietzsche’s revolution against all metaphysics. Nietzsche wants to forcefully reject the metaphysics of Plato, Descartes and Kant. By definition all metaphysics necessarily look beyond this world. Nietzsche argues that we must affirm this life—in this world—while metaphysicians encourage us to focus on ideas outside of this world. Nietzsche wants us to move beyond all metaphysics, because it focuses our attention beyond our lives.
Unlike Kant, Nietzsche rejected all forms of transcendence—of moving beyond this world. While Kant acknowledged that we couldn’t know noumena, Nietzsche claimed that we shouldn’t even care about noumena. The ultimate goal is not to transcend ‘mere appearances,’ but instead to constantly affirm the life we have the singular opportunity to undertake. Nietzsche’s Eternal Return pronounced one’s willingness to live his or her life over and over again, an infinite number of times. Nietzsche believed that this would require saying “Yes!” to all of life: pleasure, pain, luck, and misfortune. It is useful to think of Nietzsche as a full inversion of Plato’s metaphysics: instead of embracing the world of the forms, we must only seek meaning in the appearances and strive to challenge the world on one’s own terms.
Nietzsche’s bold declaration that “God is dead” was a poignant representation of his rejection of metaphysics. Nietzsche’s message was that the axial model of thought was outdated, for it encouraged the denial of living in the world. Nietzsche also held that religion, specifically Christianity, served to repress the will by making individuals feel guilt about actions. The Augustine twist on Platonism must also be rejected, Nietzsche claimed, because it searches for the City of God—when we ought live as an Übermensch in the City of Man. Nietzsche also rejected conceptions of truth as certainty. In doing so, he rejected Descartes dualism, and the transcendental ego. In Beyond Good and Evil, Nietzsche explained his skepticism towards Descartes’ cogito. Nietzsche stated, “When I analyze the process that is expressed in the sentence, ‘I think,’ I find a whole series of daring assertions that would be difficult, perhaps impossible to prove…it at any rate, has no certainty for me” (23). Nietzsche believed that Descartes rationalized his solution, pretending to have found certainty where only tautology lies. Therefore, Nietzsche questioned both the importance of a priori truths and the transcendental ego—the cornerstones of Cartesian philosophy.
Nietzsche criticized Kant for implicitly continuing the axial metaphysical tradition. In Beyond Good and Evil, Nietzsche claimed that Kant’s proof for transcendental truths is mere niaiserie allemande (German foolishness). Nietzsche claimed Kant continued the rationalist pursuit of metaphysical realism through his concept of the unknowable “thing-in-itself.” This thing-in-itself, for Nietzsche, is a “metaphysical hangover from rationalist metaphysics.” For Nietzsche, the divide between the noumenal and the phenomenal granted metaphysicians too much about the axial divide between appearance and reality. Kant believed that we are only truly human as far as we ask questions about the noumenal—and Nietzsche wanted to move beyond this conception of humanity. Instead, Nietzsche desired the Übermensch who is no longer concerned with the noumenal and instead desired to be only of this world. Nietzsche attacked the assumptions of Kant’s philosophy in order to be sure that no metaphysical conclusions could be drawn.
While Nietzsche desired to abandon metaphysics, those like Heidegger have reinterpreted Nietzsche as the last metaphysician. For Heidegger, Nietzsche symbolizes the final end of metaphysics. Nietzsche understood that his philosophy signified a paradigm shift for the future of philosophy.
“I know my fate. One day my name will be associated with the memory of something tremendous–a crisis without equal on earth, the most profound collision of conscience, a decision that was conjured up against everything that had been believed, demanded, hallowed so far. I am no man, I am dynamite.”
–Friedrich Nietzsche, Ecce Homo, “Why I Am a Destiny.”
In this passage, Nietzsche sounds unreasonably pompous, yet his influence is unprecedented. While the aforementioned philosophers have all played an enormous role in the various revolutions of metaphysics, Nietzsche was the first to actively pursue its destruction; he suitably chose the word dynamite to explain his impact.
Nietzsche’s impact is distinct from all of the other thinkers before him because Nietzsche insisted that we ought continually sweep away metaphysics. Descartes and Hume coincidentally doubted metaphysical foundations as a result of their skeptical arguments. For Nietzsche, the attack was direct and intentional. In the wake of Nietzsche, it is not useful to transcribe further revolutions in metaphysics, because after Heidegger’s account of Nietzsche, there is no metaphysics left to declare normal. Nietzsche was the first to bring an end to this grand succession of metaphysical inquiry. While Plato, Augustine, Descartes, Hume, and Kant all played a vital role in structuring and challenging periods of normal, Nietzsche can be credited with ending the discussion. By ending this discussion, Nietzsche instigated a new form of philosophy. In Essays on Heidegger and Others, Richard Rorty argues that the post-modern movement can better defined as post-Nietzschean philosophy. This final metaphysical revolution cleared the way for the entire post-modern movement. Nietzsche made it possible for future philosophers to start over and discuss something new. While previous philosophers spent time debating metaphysics, because they felt a need to justify a coherent system of metaphysics, Nietzsche eliminated this philosophical necessity—creating a calling for philosophers to tackle an entirely new set of questions.
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