Interpretations and Misinterpretations of Classical Skepticism
in Western Intellectual Tradition
Chong Ho Yu
(May 3, 2004)
According to Frede and Groarke, classical skepticism, represented by Pyrrho and Sextus Empiricus, has been widely and unfairly confused with dogmatic skepticism by many scholars. Frede traced this misunderstanding back to Cicero and St. Augustine, while Groarke related this problem to the pro-reason and pro-science mentality in Western culture. As a supplement to these notions, this article briefly illustrates a wide spectrum of interpretations and misinterpretations of Pyrrhonism by both Christian and secular scholars throughout Western intellectual history. It is fascinating but puzzling to see that Pyrrhonism was adopted by different scholars in supporting of rival claims. For example, early Christian anti-intellectualism employed Pyrrhonism to denounce secular knowledge. Byzantine scholars rejected skepticism in order to defend Orthodox spirituality. The Catholic Counter-Reformation movement saw it as a powerful weapon against Protestants. Protestants regarded it as a way to challenge the papal authority and to restore doctrinal purity. It is argued that the problem of misinterpretation should not be blamed only on the interpreters. Rather, classical skepticism carries certain properties that make it vulnerable to open interpretation. For instance, the skeptic attitude is a disposition rather than an assertion; the skeptical goal of mental tranquility is virtually unattainable. As a result, the tool of skepticism is used as an auxiliary instrument to assist other schools of thought in accomplishing their own goals.
Greek skepticism is one of the major achievements of Greek philosophy. Skepticism began with Pyrrho of Elis (360-270 BC), and thus skepticism is also known as Pyrrhonism. However, Pyrrho did not write anything; his philosophical ideas were presented in Sextus Empiricus’s Outline of Scepticism. Although many branches of Greek Academicians and Pyrrhonians treated Stoics as a common enemy, Academicians held a more radical position than Pyrrhonism in terms of epistemology and metaphysics. Due to their differences, the former is regarded as classical skepticism while the latter is associated with dogmatic skepticism.
Expert on ancient skepticism Michael Frede pointed out that many scholars confused classical skepticism with dogmatic skepticism. In opposition to the Stoic view that clear and distinct rational impressions could be the criterion of truth, classical skeptics argued that we should not take impressions to be true and thus assent should be suspended. Nevertheless, we could still live a normal life by following the probable or what appears to be the case while making no ontological commitment. On the other hand, dogmatic skepticism is a radical position which asserts nothing can be known. Obviously, there is a wide gap between these two versions of skepticism, but Frede found that most people attacked a straw man by misdirecting all criticism of skepticism to the dogmatic branch.
According to Frede, this misunderstanding could be traced back to Cicero and St. Augustine. As a dogmatic skeptic who wrote in Latin, Cicero distorted classical skepticism in support of his worldview. However, most people in the Latin West were not proficient in the Greek language, and thus the mistake of mixing classical skepticism and dogmatic skepticism was unnoticed by many. Later St. Augustine attacked dogmatic skepticism based upon Cicero’s account. Since St. Augustine was a prominent figure in Wetsern intellectual history, the West European view of skepticism was strongly influenced by his view throughout the Middle Ages.
The question of knowledge became an important issue again in the late Middle Ages due in part to Ockham’s doctrine of intuitive cognitions. Ockham accepted the position that cognitions are entities that could exist independently from the object corresponding to our cognition. In this context, scholars paid attention to Sextus Empiricus in an attempt to explore the question of the possibility of knowledge. However, the Western Europeans misperceived classical skepticism as being dogmatic, and even worse, the influence of Eastern Europe during the Renaissance reinforced this view. In brief, Frede concluded that the widespread misunderstanding of skepticism was partly owing to its Medieval heritage.
In a similar vein to Frede, Groarke was also disappointed by the fact that many scholars, such as Russell, misinterpreted the position taken by the classical Skeptic school as the dogmatic one. Like Frede, Groarke asserted that classical skeptics had no difficulty in accepting the appearance, and not surprisingly, he associated modern anti-realism with ancient skepticism. But unlike Frede, Groarke gave a different explanation to the widespread misunderstanding of the classical skeptic school:
Given the plausibility of scepticism, one must wonder why it has been so drastically misinterpreted, misunderstood, and underestimated, and why the notion that we must defeat the sceptic has become such a central feature of philosophical inquiry. The answer has more to do with the social forces that shape philosophical inquiry that with the logic of sceptic views. Scepticism is dismissed, not because it has been studied carefully and found wanting, but because it goes against the spirit of Western thought as modern philosophy has portrayed it. That account glorifies the use of reason, the possibility of science, and the human ability to establish truth, and has no patience with skeptics to attack these ideas. Instead of trying dispassionately to understand the skeptics or the subtleties of their views…philosophers treat them the way most heretics are treated—with little emphasis on the details of their views, with little or no reserve in exploiting the misunderstanding this encourages, and with rhetorical appeals to the notion that truth and reason must be saved. Even when philosophers argue for positions that resemble skepticism, they present their views as an attack on it. Not surprisingly, the resulting picture of the sceptic is an easy target and a focus of bad feeling. “Truth” and reason are always vindicated, though the truth and objectivity that the skeptics attack are relinquished in the process, replaced with a subjective notion of belief and a new definition of the word true.
While both Frede and Groarke, to some certain extent, gave plausible explanations of the widespread misunderstanding of classical skepticism, their account may not adequately illustrate the complexity of this issue. To be specific, although St. Augustine was influential throughout the Middle Ages, there was more than one interpretation of skepticism in the Latin West and the Greek East. For example, Romans treated skepticism as an ally of atheism; Christian apologetics cited skepticism to support anti-intellectualism. During the reformation, the Catholic Counter-Reformation movement viewed skepticism as a weapon against Protestantism that emphasizes personal judgment; certain Protestants also employed skepticism to promote religious toleration and to challenge the infallibility of the Catholic Church. More importantly, these skeptic orientations held by Christians were not dogmatic, because it is impossible for Christians, who have a firm belief in God, to subscribe to a worldview that nothing can be known. Rather, they replace the objective notion of truth with the subjective one.
Even though modern science rose in the West since the 17th century, embracing reason and science does not seem to be the primary motive for rejecting skepticism or misinterpreting classical skepticism as being dogmatic. For example, Hume adopted a naturalistic approach to reject dogmatic skepticism because believing is said to be our undeniable and natural inclination. In other words, Hume misinterpreted and refused classical skepticism on psychological rather than philosophical ground. Interestingly enough, in the early 20th century thinkers who were sympathetic to empiricism, logical positivism, and anti-realism did not see skepticism as anti-reason or anti-science. Instead, classical skepticism was praised as a precursor to the anti-metaphysic position embraced by empiricism, behaviorism, pragmaticism, and logical positivism. In brief, acceptance, rejection, and distortion of ancient skepticism could not be simplified to the influence of St. Augustine and its Medieval heritage or an obsession with reason, objectivity, and scientific knowledge.
This objective of this article is to illustrate how skepticism was interpreted by different people throughout different periods of history, including thinkers who were in rival parties. It is important to note that it is not the goal of this article to evaluate which thinker’s interpretation is closer to the original position of the classical skeptic school, nor will I place an emphasis on analyzing why these thinkers tend to misinterpret ancient skepticism. Actually, different eras generate different central issues, and as a result, different concerns lead to different conclusions based on the same ancient philosophy. However, certain inherent properties of classical skepticism play a major role in inviting this wide spectrum of interpretation and misinterpretation. To be specific, the skeptic is a disposition rather than an assertion; the skeptical goal of mental tranquility is virtually unattainable. As a result, the tool of skepticism is used as an auxiliary instrument to assist other schools of thought in accomplishing their own goals.
Tertullian and Anti-intellectualism
Although the Roman Empire inherited the Greek culture, Romans were much less interested in intellectual inquiry than Greeks, and not surprisingly, classic texts were not seriously studied by Romans. Skepticism was mentioned in only a few lines by Emperor Julian and was treated negatively, since he viewed skepticism as an ally of atheism. Interestingly enough, certain Christian thinkers did not see skepticism as an ally of atheism. On the contrary, Tertullian borrowed the notion of skepticism to downplay the value of secular knowledge. His anti-intellectualism was manifested in the following passage:
For philosophy is the material of the world’s wisdom, the rash interpreter of the nature and dispensation of God. Indeed heresies are themselves instigated by philosophy… What indeed has Athens to do with Jerusalem? What has the Academy to do with the Church? What have heretics to do with Christians? Our instruction comes from the porch of Solomon, who had himself taught that the Lord should be sought in simplicity of heart. Away with all attempts to produce a Stoic, Platonic, and dialectic Christianity! We want no curious disputation after possessing Christ Jesus, no inquisition after receiving the gospel! When we believe, we desire no further belief. For this is our first article of faith, that there is nothing which we ought to believe besides (emphasis added).
As the preceding passage illustrates, Tertullian was hostile to Stoics and Plato, but not Pyrrhonians. For Tertullian the state of ignorance of secular knowledge was compatible with the final aim of ataraxia--mental transquality—proposed by Pyrrhonians. Curiosity is a vice that could disturb the mental tranquility achieved by knowing nothing except God. However, Floridi pointed out that the differences between classical skepticism and Christianized skepticism are substantial. Once doubt has been instilled, classical skepticism steps back into suspension of judgment while Christianized skepticism leaps forward into faith. The Christian thinker did not deny the full intelligibility of the ultimate reality, which is the spiritual realm; rather he ranked the pursuit of secular knowledge much less valuable than the love and worship of God. The same theme, as illustrated later, recurred throughout the era of Reformation.
Agathias and Anti-metaphysics
At the end of the fourth century, Academic skepticism transmitted in Latin had become the brand of skepticism known to philosophers and theologians, at the expense of classical skeptics. Greek texts became inaccessible to most people, and as a result, the classical skeptic work was largely forgotten by the Latin West throughout the Middle Ages. Fortunately, scholars in the Orthodox East were versed in the Greek language, and occasionally the work by classical skeptics was cited in intellectual debate. For example, in the 6th century Byzantine historian Agathias (532-580) praised Pyrrho and Sextus Empiricus for their dismissive attitude toward useless and endless debates over unsolvable questions. Agathias’s academic background and personal beliefs could help us to appreciate why he endorsed the classical skeptic view. At the age of thirty Agathias turned to the writing of history and composed a five-volume book entitled On the Reign of Justinian, which relates to the events of 552-558, such as the wars with the Goths, Vandals, and Franks, as well as those against the Persians and the Huns. As a prudent historian, he relied on eyewitness accounts as well as other verifiable sources as the basis of reconstructing historical facts, and thus he saw the classical skeptic school as his ally in opposition to metaphysical speculations. Obviously, he did not read the classical text carefully enough to learn that even eyewitness accounts are doubted as genuine knowledge by classical skeptics. However, it appealed to him because in his lifetime he experienced mass destruction by wars and to him there were many more urgent matters than metaphysical speculations. Also, Agathias was a pagan, not a Christian, and there is a good match between the skeptic philosophy and his suspension of judgment regarding non-verifiable, spiritual matters.
Orthodox Spirituality and Negative Epistemological Dogmatism
As Frede mentioned, Ockhamism generated the impetus for studying skepticism during the 14th century. In Ockham’s view, God is omnipotent and thus nothing is as it is necessarily; everything could have been otherwise. This raised a number of doubts about the nature of reality and the criterion of truth. In this academic context Nicholas of Autrecourt worked on the skeptical theme and subsequently attracted a significant amount of scholarly attention. In the same century, Byzantine culture also revived the intellectual debate about skepticism. Religious controversies and a renewal of literary studies are probably behind the revival of interest in skepticism.
After studying Sextus Empiricus, Theodore Metochites (1270-1332) and his student Nicephorus Gregoras (1290-1358) condemned Sextus’s theses. They asserted that doubt, in contrast to faith, was a disease that could threaten the church. Nevertheless, Metochites still extracted certain notions from Sextus’s philosophy in rendering his own theology. It is important to point out that distrust of human rationality and judgment by classical skeptics aligns to some degree with the doctrine of the fall of humanity caused by original sin. No wonder Metochites repeatedly emphasized that the intellect is inseparably connected to the irrational soul, and constantly hampered by it. Metochites’s epistemological pessimism is tied to his partial defense of ancient skepticism. However, the similarities end there. Metochites misconstrued skepticism as “negative epistemological dogmatism,” embracing the notion that nothing can be known. He was a realist who held true the realms of natural phenomena and human life, and maintained that by divine revelation knowledge of reality is possible. Another Byzantine scholar, St. Gregory Palamas (1296-1359), argued that knowledge of God can be obtained by grace, and thus he also disliked the skeptic view of Pyrrhon. Palamas promoted a form of spirituality known as “Hesychasm,” which means “inner stillness” or “inner peace.” Needless to say, classical skepticism, which is uninterested in groundless assertions, was at odd with Orthodox mysticism.
Michel Montaigne, Counter-Reformation and Catholic Pyrrhonism
In the 16th century, Catholic scholars such as Gentianus Hervetus and Michel Montaigne viewed skepticism as a powerful weapon for religious controversy in defense of Catholic orthodoxy. Montaigne (1533-1592) was regarded as the most significant figure in the 16th century revival of ancient skepticism. Montaigne insisted that true religion can only be based on faith and that any human foundation for religion, such as rationality, is too weak to enable us to receive divine knowledge. In support of his fideism, Montaigne quoted St. Paul’s declamation in First Corinthians 1:19-21: “For it is written, I will destroy the wisdom of the wise, and will bring to nothing the understanding of the prudent. Where is the wise? Where is the scribe? For after that in Wisdom of God the world by wisdom knew not God, it pleased God by the foolishness of preaching to save them that believe.” Along with citation of St. Paul’s text, Montaigne offered arguments from Sextus Empiricus and other ancient skeptics to demonstrate how unreliable human knowledge is and how futile intellectualism is. Contrary to Eastern Orthodox scholars, not only did Montaigne not see skepticism as a disease, but he also defended Pyrrhonism with an explanation of its value for religion. To Montaigne, Pyrrhonism was different from negative epistemological dogmatism as described by Metochites. Pyrrhonism stated that any assertion, if successful, shows the opponent’s ignorance; if unsuccessful, their own ignorance. Montaigne asserted that this mentality is the finest of human achievements and the most compatible with true religion.
Montaigne’s skepticism did not arise out of a vacuum. He was deeply upset by the brutality and chaos resulting from religious wars between Catholics and Protestants. In 1586 Catholic forces besieged Castillon, a Protestant stronghold near where Montaigne lived, and he found the actions of these plunderers loathsome. Further, Montaigne was skeptical of Calvinists’ insistence upon knowing God’s will. This situation of anomie fed Montaigne’s doubt about the validity and legitimacy of the Protestant claims. To Montaigne, since the complete skeptic had no positive views, he could not have the wrong views. And since the Pyrrhonians accepted the laws and customs of his community, he would accept Catholicism. More importantly, the complete skeptical mind was in the ready mode for receiving divine revelation. In other words, skepticism was interpreted by him as conservatism. Since one is incapable of judging anything, the best course of action is to stay in the current position assigned by God.
Nevertheless, according to Schiffman, Montaigne did not straightly equate the true religion to the Catholic Church and the Pope. Rather, he tried to make Christians see themselves as nothing but mere creatures incapable of knowing God’s will. Schiffman asserted that Montaigne was not a “Catholic Pyrrhonist”; actually it was Montaigne’s followers who identified with Pyrrhonism, thinking that they had found the best defense against Reformation. After the Council of Trent in 1564, Pyrrhonism was employed by Catholic scholars like Francoise Veron as a “machine of war” to remove two Protestant principles, namely, Sola Scriptura and personal judgment. For Catholic Pyrrhonians, individual interpretation of the Scripture was doomed to open a Pandora’s Box, while personal judgment was unreliable due to our corrupted intellect. Interestingly enough, Protestant intellectuals adopted the same philosophy to deny the notion that Catholic authority is the criterion of truth. Sextus was doubtful of the existence of a criterion of truth. He further maintained that even if such a criterion exists, who should set the criterion remains an unresolved question. Hence, for Protestants, Catholic Pyrrhonians violated the principle of skepticism by their self-appointment of sole authority. Nevertheless, Montaigne’s version of Pyrrhonism strongly influenced the Catholic Church, and to some certain extent, Montaignians shared a common thread with Protestants in their belief that a skeptical attitude depresses our intellectual pride and prepares us to receive divine gifts. Not only did Catholic Bishop Pierre-Daniel Huey stand firmly in the Montaigne tradition, but his contemporary Pierre Bayle, who was a Calvinist, also utilized skepticism to promote fideism.
Pierre Bayle, Religious Toleration and Calvinism
In the late 17th century, the revival of skepticism had penetrated both philosophy and theology. For instance, in philosophy Simon Foucher (1644-1696) raised questions about the Cartesian system using the arguments he founding both the Academic and the Pyrrhonian skeptic schools. In theology, English Protestant thinker William Chillingworth (1602-1644) was also a fan of skepticism. Once he left Protestantism for Catholicism, and then left the Catholic Church for the Anglican Church. In both conversions his Pyrrhonian attitude led him to uncertainty in religious doctrines. After he re-examined the philosophy of Sextus Empiricus, he realized that although both Protestantism and Catholicism could not be proven to be the absolute truth, he could still justify his inclination toward Protestantism based upon probabilistic inferences. But he rejected the Catholic Church for its insistence upon certainty and infallibility of doctrines.
French Calvinist Pierre Bayle (1647-1706), who was called a “super-skeptic” by Popkin, was a prominent figure in the Pyrrhonian movement. Like Chillingworth, at first Bayle was a Calvinist, but later he abandoned Protestantism for Catholicism. A few months later, he returned to Calvinism. Due to the French law forbidding conversion from Catholicism to Calvinism under penalty of death, Bayle was forced to flee from city to city in Holland. During his exile between 1684 and 1685, his father and brothers died as a result of religious persecution. Owing to his suffering he devoted tremendous efforts to writing against superstition, dogmatism, and intolerance. Bayle presented himself as an advocate of universal toleration, calling for toleration of even Jews, Quakers, Unitarians, and atheists. After 1685 when tolerance for Calvinism ceased in France, Bayle sought to influence European opinion against Louis XIV, who wanted to purge his country of heresy. He was also vocal in opposition to his Protestant friend Pierre Jurrieu’s attempt to enforce Calvinist orthodoxy in his home country. Dogmatism of religious fanatics played a vital role in driving Bayle towards Pyrrhonism, whose theme of suspension of judgment paves the way to religious toleration.
As mentioned before, Bayle was converted from Calvinism to Catholicism and then returned to his original sect. Bayle did not switch religious affiliations arbitrarily; rather, he made these decisions based on serious intellectual consideration. Comparing Calvinism to Catholicism, Bayle was convinced that the Calvinist emphasis on the corruptness of human nature, both morally and intellectually speaking, could help the boastful to be humble. Following the path of classical skeptics, he interrogated every argument for all theological claims. His strategy was to analyze and dissolve any theory on its own terms. In doing so, he relied much more on the anti-metaphysical sections of Sextus’s writings than on the epistemological ones. In his process, every aspect of a theory was thoroughly inspected, and after persistent questioning, the theory disintegrated into insurmountable contradictions. To Bayle an intellectual inquiry was like peeling an onion until at last nothing was left. But unlike classical skeptics, Bayle offered a transcendental salvation. Bayle agreed with the classical skeptics that reason fails to make the world intelligible. Nevertheless, revealed knowledge leads us to reality and truth.
Bayle contended that rational people find the claim “Nothing comes from nothing” to be plain truth, but it would be completely refuted by Creation ex nihilo (creation out of nothing). In addition, by common sense no one would dispute that the summation of “three” does not equal “one,” yet the doctrine of the Trinity denies this intuitive notion. In ethics, it seems ironic that one ought to prevent evil, but God does not stop all evils in the world. Evidently, people should not be punished for crimes that they did not commit, but the doctrine of Original Sin contradicts the preceding notion.
Inspired by classical skeptics who had reservations about making inferences beyond appearance, Bayle developed the notion of doctrinal minimalism, an attenuation of formal belief that sought the barest doctrinal necessities. He could say that Christ was the Messiah, but he would not make further elaboration of what this statement means.
Interestingly enough, Bayle insisted that he was not advocating Pyrrhonism, but only orthodox Calvinism. Once the Protestant leader, La Placette, asked Bayle whether he were a Pyrrhonist, and Bayle shook his head and replied, “I know too much to be a skeptic and too little to be a dogmatist.”  Put simply, for Bayle, skepticism is the means and Calvinism is the end. Through Pyrrhonism the futility of human rationality is exposed, but Christian faith opens a door to redemption. Moreover, Pyrrhonism can help us to strip all erroneous conventions from religious institutions. Bayle always compared Calvinist doctrinal simplicity and individual conscience to Catholic idolatry, superstition, and autocracy. But at the same time, he encouraged his Calvinist colleagues to maintain a skeptical mind to all human teachings and warned them not to fall into the same traps of Catholic corruption.
David Hume, Irrational Nature and Psychological Tranquility
David Hume (1711-1776), a major philosopher in the 18th century, construed skepticism in a dogmatic manner. Sextus Empiricus attempted to list a series of arguments and then suspended judgment on them, but Hume misinterpreted Sextus’s position as dogmatically holding that all questions are unanswerable. Moreover, Hume’s rendering of Pyrrhonism omits any reference to the basis that Pyrrhonism offers for deciding practical questions once the skeptical attitude has been adopted. Sextus maintained that the skeptic could accept appearances undogmatically and live naturally. This misinterpretation was partly due to the fact that Hume’s knowledge of Greek was inadequate for reading Sextus. According to Olshewsky, in Hume’s time at least two well-written texts on ancient skepticism were available: Thomas Stanley’s The History of Philosophy (1655) and Pierre Bayle’s Dictionnaire Historique et Critique (1695). Olshewsky asserted that the accounts of both Stanley and Bayle match up well with the contrast between dogmatic skepticism and classical skepticism in Sextus’s writing, and therefore it is implausible that Hume interpreted Pyrrhonism with reference to these texts. Actually, misinterpretation of classical skepticism by Hume is tied to the intellectual atmosphere in the 17th century, maintaining that science and philosophy were enterprises of producing factual knowledge based on objective inquiry. In reaction to this impassionate attitude, Hume identified irrationality as our human essence and refused skepticism on naturalistic and psychological grounds.
Hume is well known for his doubt of the conventional notion of causation. To Hume many so-called cause and effect relationships are nothing more mere association. Hume drew support from Pyrrhonism in his anti-causation claim: All our evidence of causation is based upon a conjunction at a given moment, but there is no rational basis to believe that this association have been constant in the past and will remain so in the future. Like his predecessors, Hume attempted to use Pyrrhonism to demonstrate the inadequacy of human reasoning. But Hume disagreed with Pyrrhonians that suspension of judgment could lead to mental tranquility. In contrast, Hume argued that a complete skeptic will not obtain peace of mind at all, but instead will be insane; because humans are led by a natural instinct to suppose that there is an external reality existing independently of our sense; Pyrrhonism goes against our nature. On one hand, Hume accepted the gloomy view that rationality could not bring any intellectual inquiry to a conclusive closure. On the other hand, Hume held that a complete skeptical attitude is not applicable to common sense beliefs and everyday life. He maintained that to lead a normal life day by day we must hold opinions instead of suspending judgment since nature forces us to do the former. It is not a question of what we should do philosophically, but what we ought to do psychologically. Paradoxically, although we cannot determine the true cause and effect relationships among events and objects, it is nature and not philosophical reasoning that leads us to make all causal inferences. Hume went even further to claim that there is something right about the fact that we function irrationally.
Interestingly enough, unlike Montaigne and Bayle who employed skepticism to defend religion, Hume was a consistent anti-religionist. Although he contended that belief in the existence of God was natural, he characterized all religion as the product of fear and error. Hume classified religions into two types, namely, popular religion and true religion. Popular religion develops from polytheism to monotheism, not by reasoning, but by a gradual exaggeration of one of the deities whom people regard as the most powerful and dependable. True religion, in contrast, does not arise from fear or child-like dependency; rather it arises from recognition of the order in the universe. Nonetheless, both religions are based upon a universal propensity to believe in an invisible and omnipotent being. Besides religious faith, humans also possess many other irrational beliefs. To Hume, our irrational nature supercedes the Pyrrhonian attitude. By embracing irrational natural instincts and mechanisms human societies can continue to persevere.
Empiricism, Positivism, Pragmatism, Behaviorism,
Phenomenalism, and Epistemological Anarchism
There is no doubt that many modern philosophers were hostile to skepticism due to misinterpretation. However, many others read Sextus Empiricus correctly and treated him as an ally. In the 19th century the supposition that Pyrrhonists live in accordance with justified beliefs based on non-epistemic impressions had generally prevailed among commentators on Greek skepticism. For example, in 1869 Norman MacColl published a work in which he attributed the notion of accepting the appearance to Pyrrhonism and subjected it to a Kantian criticism. Later the Pyrrhonian view was seen as highly meritorious when it was associated with empiricism. Mary Mills accepted MacColl’s account of Pyrrhonism but was sympathetic to the Pyrrhonian position. In 1929 she published a book which claimed that the Pyrrhonian way was virtually identical to the modern scientific method. In 1941 Roderick Chisholm praised Sextus’s contributions to philosophy and presented him as a precursor of empiricism, positivism, and other modern schools of thought:
His most significant contributions are: first, the positivistic and behavioristic theory of signs which he opposed to the metaphysical theory of the Stoics; secondly, his discussion of phenomenalism and its relation to common sense claims to knowledge; and, thirdly, his account of the controversy over the principle of extensionality in logic, where the anticipation of contemporary doctrines is perhaps most remarkable.
Chisholm praised Sextus for his anti-metaphysical position by saying that his theory “was a clear statement of the essential principles of positivism, pragmatism, and behaviorism.” To him ancient skeptics and Reichenbach shared a high degree of resemblance since both held that we can make probable assertions about non-empirical objects. Such assertions have an initial probability if based upon clear and distinct impressions. This probability can be increased by corroborating the reports of the different senses and by investigating all the conditions under which the observation occurs. Thus, we can attain a reasonably high degree of probability for some assertions.
In philosophy of science, Sextus Empiricus was highly regarded by Alan Bailey. Bailey compared Sextus to Paul Feyerabend by saying, “Feyerabend, despite claiming to be an epistemological anarchist rather than a sceptic, is perhaps the 20th century philosopher who most closely conforms to the role and strategy of Sextus’ Pyrrhonist.” Feyerabend was skeptical of scientific progress, but he also rejected Karl Popper’s philosophy of science by showing that his falsificationism would actually have hindered science from making progress. A common counter-argument against Feyerabend is that if he doubts scientific progress, then accusing Popperian philosophy of science of stalling scientific progress is contradictory. Nevertheless, Bailey asserted that Feyerabend’s position is defensible because it resembles Sextus’s methodology. Sextus questioned the criterion of truth, which at first glance is self-defeating, because there would be no criterion for Sextus to deny other people’s criteria. Bailey argued that Sextus might deny all criteria but still challenge his opponents because they accept some sort of criteria. In short, the game rule applies to opponents only. By the same token, although Feyerabend dismissed scientific progress, he could use it to challenge Popper because “progress” and “falsification” are internally consistent within the Popperian system. In short, to Bailey Sextus and Feyerabend are allies in terms of epistemological anarchism.
It is out of the scope of this article to discuss whether classical skepticism is compatible with modern empiricism, positivism, pragmatism, behaviorism, phenomenalism, and epistemological anarchism. Nonetheless, it is fascinating to see that Mills and Chisholm, unlike Hume, did not view classical skepticism as the end of the possibility of knowledge, and that modern philosophers from a wide variety of schools regarded Sextus as their ally.
As illustrated above, interpretation and misinterpretation of ancient skepticism are so diverse that not only is a coherent movement absent, but also implications and conclusions made by different skeptics and anti-skeptics are found to contradict each other. Romans saw Pyrrhonism as atheistic in essence. Early Christian anti-intellectualism employed Pyrrhonism to denounce secular knowledge in support of pursing spiritual knowledge. Byzantine scholars rejected skepticism in order to defend Orthodox spirituality. The Catholic Counter-Reformation movement considered it a powerful weapon against Protestants. Protestants regarded it as a way to challenge papal authority and to restore doctrinal purity. Hume accepted the skeptics’ implication that there is no certainty of knowledge, but rejected this attitude in favor of psychological comfort. Modern philosophers found compatibility between Pyrrhonism and empiricism/positivism, as well as many other schools. In brief, the entire picture is much more complicated than Frede’s assertion of St. Augustine’s distortion and Medieval heritage, or Groarke’s thesis that scholars rejected skepticism out of a pro-science and pro-rationality agenda. No wonder after reviewing theories of skeptics spanning across the 16th to 18th centuries, Stunkel made this comment:
If Montaigne, Bayle, and Hume shared one thing in common, it was their sympathy for a common life and dislike of intellectual rigidity. Otherwise, their agendas seldom converged…They did not think about the world in the same frame of reference, except for a common attachment to the surviving literary heritage of classical antiquity…What they shared was a provisional commitment to reason and a rejection of absolutes.” 
Even worse is that certain claims made by some skeptics are so ambiguous that modern scholars cannot tell exactly what they mean. For example, while Popkin considered Montaigne to be a Catholic Pyrrhonian who defended the Church orthodoxy, Schiffman saw Montaignian skepticism as a tool for self-examination of our inner world; the apologetic character of Catholic Pyrrhonism was found in his followers instead. Further, Bracken pointed out that researchers could not come to consensus on whether Pierre Bayle was a skeptic or not. Similarly, Kenshur questioned whether Bayle’s fideism was the telos of the skeptical method or an alternative to it. Moreover, although Hume is said to be a skeptic in causal inferences and certainty of knowledge, he was a skeptic of skepticism. On one hand, he claimed to be pessimistic that the objective of inquiry he identified can be achieved. On the other hand, he was also seen as a supporter of Newtonian system of science and set out to become Newton’s counterpart in modern sciences.
The diversity of interpretation and misinterpretation of classical skepticism may be partly due to certain attributes in Pyrrhonism. First, the Academic version of the skeptical notion “nothing can be known” is self-defeating because this statement seems to be a notion of knowledge claim. This statement has the same self-refuting effect as putting up a sign saying “Please ignore all signs” or telling people “Don’t believe anything I say.” The Pyrrhonians attempted to avoid the paradox of dogmatic skepticism by presenting their idea as a disposition or way of thinking rather than a doctrine. While this openness frees followers of Pyrrhonism from dogmatism, it also opens itself to interpretation or even abuse. The character of Pyrrhonism as dispositional instead of doctrinal makes classical skepticism an auxiliary tool to other thoughts in philosophy and theology. It is fascinating to see that no philosopher and theologians mentioned above adopted Pyrrhonian as their central identity. Catholicism was primary to Montaigne; skepticism was only secondary to him. Bayle admitted that he was more a Calvinist than a skeptic. Although Sextus Empiricus was considered an ally of empiricism, logical positivism, and anti-realism, philosophers in those camps would rather call themselves empiricist, logical positivist or anti-realist than skeptic. Bluntly speaking, the notion of suspension of judgment calls for no further course of action. The skeptical disposition can at most serve as a starting point for thinkers in the process of intellectual inquiry, but other schools of thought must be introduced in order to lead inquirers to go beyond the point of departure. When a branch of philosophy is used as a tool to support another school of thought, it is expected that the former will be somewhat twisted to serve the latter. The selective use of skepticism can easily be found in the preceding scholars. For example, by using Pyrrhonism to humble himself, Bayle regarded the doctrines of Trinity and Original Sin as divine revelation above human intellect. However, by using the same skeptical attitude as a tool to challenge Catholic authority, he mocked the Catholic doctrine of Transubstantiation as absurdity rather than respecting it as divine mystery.
One may argue that Pyrrhonism did offer a goal rather than a starting point or a means. To Pyrrhonians the end product of the process of doubt is mental tranquility, also known as ataraxia, devoid of contemplating with rival claims. However, this goal is too unrealistic or too unnatural to achieve, and thus it is not surprising to see many scholars subscribing to only the skeptic way of inquiry, but not the goal of equanimity. Kenshur argued that the fact that the balancing of opposing propositions conduces to the goal of ataraxia would at least seem to imply a truth claim. We have to assume that we could eventually collect adequate information in support of making a conclusion that all opposing arguments have been exhausted and hence the search has to be given up. However, if we constantly maintained a skeptical examination of every claim and every piece of evidence, the search would go on and on forever, and the goal of mental calmness would never be reached. As mentioned before, Hume had pointed out that the skeptical goal of mental tranquility is so unnatural that the possibility of achieving it is extremely remote. Hume is not alone. Nietzsche also pointed out that every skeptical tendency constitutes a great danger for life and it is better to assert than to doubt.  By the same token, American pragmaticist Charles Sanders Peirce said that we are satisfied with stable beliefs rather than doubts. Although knowledge is fallible in nature, and in our limited lifetime we cannot discover the ultimate truth, we still have to fix our beliefs at certain points rather than doubting infinitely. Actually, from early Christian anti-intellectualism to Calvinism and Catholicism during the Reformation, no Christian thinkers regarded the goal of ataraxia as attainable; all of them substituted fidelism for it. Without a plausible ultimate objective that can attract undivided commitment, Pyrrhonism remains nothing more than a tool to assist other philosophies and theologies to achieve their own goals. Thus, it is not surprising to see such a wide array of interpretations and misinterpretations of skepticism when different scholars manipulate it for different orientations of ultimate concerns.
 Sextus Empiricus, Outlines of Scepticism (Cambridge: Cambridge University Press, 1994).
 Michael Frede, “The Sceptic’s two Kinds of Assent and the Question of the Possibility of Knowledge,” Essays in ancient philosophy, ed. Michael Frede (Minneapolis, MN: University of Minnesota Press, 1987), 127-152; “The Sceptic’sBeliefs,” The Original Sceptics: A Controversy, ed. Myles Burneyeat and Michael Frede (Cambridge: Hackett Publishing Company, 1997), 1-24.
 Leo Groarke, Greek Scepticism: Anti-Realist Trends in Ancient Thought (Buffalo, NY: McGill-Queen’s University Press, 1990): 153.
 Luciano Floridi, Sextus Empiricus: The Transmission and recovery of Pyrrhonism (Oxford: Oxford University Press: 2002), 13.
 Quoted by J. Stevenson, A New Eusebius: Documents Illustrating the History of the Church to AD 337 (London: SPCK: 1987), 166-167.
 Floridi, 2002, 15.
 Ibid., 21.
 Borje Byden, Theodore Metochites' Stoicheiosis Astronomike and the Study of Philosophy in Early Palaiologan Byzantium (Doctoral Dissertation, Göteborg University: 2001).
 John Meyendorff, St. Gregory Palamas and Orthodox Spirituality (Crestwood, N.Y.: St. Vladimir's Seminary Press, 1999).
 Richard Popkin, The History of Scepticism: from Savonarola to Bayle (Oxford: Oxford University Press, 2003), 44-63.
 Kenneth Stunkel, “Montaigne, Bayle, and Hume: Historical Dynamics of Skepticism,” European Journal, 3 (1998): 43-64.
 Popkin, 2003, 51.
 Zachary Schiffman, “Montaigne and the Rise of Skepticism in Early Modern Europe: A Reappraisal,” Journal of History of Ideas, 45 (1984): 499-516.
 Stunkel, 1998, 49.
 R. J. Hankinson, The Sceptics (London: Routledge, 1995), 195-196; Sextus disputed against the dogmatist’s claim that man should be the criterion of all things by asking “which man?”
 Popkin, 2003, 274-282.
 Ibid., 274-275.
 Ibid., 65.
 Ibid., 283.
 Richard Popkin, “The Skeptical Precursors of David Hume,” Philosophy and Phenomenological Research, 16 (1955): 61-71; Stunkel, 1998, 48.
 Stunkel, 1998, 56.
 Popkin, 2003, 289.
 Ibid., 2003, 283-302.
 Popkin, 1955, 64-65.
 Stunket, 1998, 56.
 Popkin, 1955, 64-67.
 Stunkel, 1998, 55.
 Leo Groarke and Graham Solomon, “Some Sources for Hume’s Account of Cause,” Journal of the History of Ideas, 52 (1991), 645-663.
 Thomas Olshewsky, “The Classical Roots of Hume’s Skepticism,” Journal of the History of Ideas, 52 (1991), 269-287.
 Stunkel, 1998, 57.
 Richard Popkin, “David Hume: His Pyrrhonism and His Critique of Pyrrhonism,” Philosophical Quarterly, 1(1951): 385-407.
 Popkin, 1951, 391-395; Loeb argued that besides David Hume, Rene DesCartes and Charles Sanders Peirce also adopted a naturalistic approach to accomplish intellectual tranquility. See Louis Loeb, “Sextus, DesCartes, Hume, and Peirce: On Securing Settled Doxastic States,” Nous, 32 (1998), 205-230.
 Stunkel, 1998, 50.
 Popkin, 1951, 397-400.
 Alan Bailey, Sextus Empiricus and Pyrrhonean Scepticism (Oxford: Clarendon Press, 2002), 214-215.
 Roderick Chisholm, “Sextus Empiricus and Modern Empiricism,” Philosophy of Science, 8 (1941), 371-384.
 Chisholm, 1941, 372.
 Ibid., 378-379
 Alan Bailey, Pyrrhonean Scepticism and the Self-Refutation Argument,” Philosophical Quarterly, 40 (1990): 27-44.
 Bailey, 1990, 40.
 Ibid., 40-41.
 Stunkel, 1998, 43.
 Harry Bracken, “Bayle not a Sceptic?” Journal of the History of Ideas, 25 (1964): 169-180.
 Oscar Kenshur, “Pierre Bayle and the Structure of Doubt,” Eighteenth Century Studies, 21 (1988) 297-315.
 Loeb, 1998, 206; Stunkel, 1998, 52-54.
 Bracken, 1964, 177.
 Kenshur, 1988, 298-299..
 Nietzsche, Friedrich. The Gay Science. Trans. E. S. Dallas (London: Chapman and Hall, 1866).
 Charles Sanders Peirce, “The Fixation of Belief,” Popular Science Monthly, 12 (1877) 1-15.