Scepticism as a philosophical view, rather than as a series of doubts concerning traditional religious beliefs, had its origins in ancient Greek thought. In the Hellenistic period, the various sceptical observations and attitudes of earlier Greek thinkers were developed into a set of arguments to establish either (1) that no knowledge was possible or (2) that there was insufficient and inadequate evidence to determine if any knowledge was possible, and hence that one ought to suspend judgment on all questions concerning knowledge. The first of these views is called Academic scepticism, the second Pyrrhonian scepticism.
Academic scepticism, so called because it was formulated in the Platonic Academy in the third century B.C.E., developed from the Socratic observation “All I know is that I know nothing.” Its theoretical formulation is attributed to Arcesilas, c. 315–241 B.C.E., and Carneades, c. 213–129 B.C.E., who worked out a series of arguments, directed primarily against the knowledge claims of the Stoic philosophers, to show that nothing could be known. As these arguments have come down to us, especially in the writings of Cicero, Diogenes Laertius, and Saint Augustine, the aim of the Academic sceptical philosophers was to show, by a group of arguments and dialectical puzzles, that the dogmatic philosopher (i.e., the philosopher who asserted that he knew some truth about the real nature of things) could not know with absolute certainty the propositions he said he knew. The Academics formulated a series of difficulties to show that the information we gain by means of our senses may be unreliable, that we cannot be certain that our reasoning is reliable, and that we possess no guaranteed criterion or standard for determining which of our judgments is true or false.
The basic problem at issue is that any proposition purporting to assert some knowledge about the world contains some claims that go beyond the merely empirical reports about what appears to us to be the case. If we possessed any knowledge, this would mean, for the sceptics, that we knew a proposition, asserting some nonempirical or transempirical claim, that we were certain could not possibly be false. If the proposition might be false, then it would not deserve the name of knowledge but only that of opinion, that is, that it might be the case. Since the evidence for any such proposition would be based, according to the sceptics, on either sense information or reasoning, and both of these sources are unreliable to some degree, and no guaranteed or ultimate criterion of true knowledge exists, or is known, there is always some doubt that any nonempirical or transempirical proposition is absolutely true, and hence constitutes real knowledge. As a result, the Academic sceptics said that nothing is certain. The best information we can gain is only probable and is to be judged according to probabilities. Hence Carneades developed a type of verification theory and a type of probabilism that is somewhat similar to the theory of scientific “knowledge” of present-day pragmatists and positivists.
The scepticism of Arcesilas and Carneades dominated the philosophy of the Platonic Academy until the first century before Christ. In the period of Cicero’s studies, the Academy changed from scepticism to the eclecticism of Philo of Larissa and Antiochus of Ascalon. The arguments of the Academics survived mainly through Cicero’s presentation of them in his Academica and De Natura Deorum and through their refutation in St. Augustine’s Contra Academicos, as well as in the summary given by Diogenes Laertius. The locus of sceptical activity, however, moved from the Academy to the school of the Pyrrhonian sceptics, which was probably associated with the Methodic school of medicine in Alexandria.
The Pyrrhonian movement attributes its beginnings to the legendary figure of Pyrrho of Elis, c. 360–275 B.C.E., and his student Timon, c. 315–225 B.C.E. The stories about Pyrrho that are reported indicate that he was not a theoretician but rather a living example of the complete doubter, the man who would not commit himself to any judgment that went beyond what seemed to be the case. His interests seem to have been primarily ethical and moral, and in this area he tried to avoid unhappiness that might be due to the acceptance of value theories and to judging according to them. If such value theories were to any degree doubtful, accepting them and using them could only lead to mental anguish.
Pyrrhonism, as a theoretical formulation of scepticism, is attributed to Aenesidemus, c. 100–40 B.C.E. The Pyrrhonists considered that both the dogmatists and the Academics asserted too much, one group saying “Something can be known,” the other saying “Nothing can be known.” Instead, the Pyrrhonians proposed to suspend judgment on all questions on which there seemed to be conflicting evidence, including the question whether or not something could be known.
Building on the type of arguments developed by Arcesilas and Carneades, Aenesidemus and his successors put together a series of “tropes,” or ways of proceeding to bring about suspense of judgment on various questions. In the sole surviving texts from the Pyrrhonian movement, those of Sextus Empiricus, these are presented in groups of ten, eight, five, and two tropes, each set offering reasons why one should suspend judgment about knowledge claims that go beyond appearances. The Pyrrhonian sceptics tried to avoid committing themselves on any and all questions, even as to whether their arguments were sound. Scepticism for them was an ability, or mental attitude, for opposing evidence both pro and con on any question about what was nonevident, so that one would suspend judgment on the question. This state of mind then led to a state of ataraxia, quietude, or unperturbedness, in which the sceptic was no longer concerned or worried about matters beyond appearances. Scepticism was a cure for the disease called dogmatism, or rashness. But, unlike Academic scepticism, which came to a negative dogmatic conclusion from its doubts, Pyrrhonian scepticism made no such assertion, merely saying that scepticism is a purge that eliminates everything including itself. The Pyrrhonist, then, lives undogmatically, following his natural inclinations, the appearances he is aware of, and the laws and customs of his society, without ever committing himself to any judgment about them.
The Pyrrhonian movement flourished up to about 200 C.E., the approximate date of Sextus Empiricus, and flourished mainly in the medical community around Alexandria as an antidote to the dogmatic theories, positive and negative, of other medical groups. The position has come down to us principally in the writings of Sextus Empiricus in his Hypotyposes (Outlines of Pyrrhonism) and the larger Adversus mathematicos, in which all sorts of disciplines from logic and mathematics to astrology and grammar are subjected to sceptical devastation.
The two sceptical positions had very little apparent influence in the post-Hellenistic period. The Pyrrhonian view was little known in the West until its rediscovery in the late fifteenth century, and the Academic view was mainly known and considered in terms of St. Augustine’s treatment of it. Prior to the period I shall deal with, there are some indications of a sceptical motif, principally among the antirational theologians, Jewish, Islamic, and Christian. This theological movement, culminating in the West in the work of Nicholas of Cusa in the fifteenth century, employed many of the sceptical arguments in order to undermine confidence in the rational approach to religious knowledge and truth.
The period I shall treat, 1450–1710, is certainly not the unique period of sceptical impact on modern thought. Both before and after this time interval, one can find important influences of the ancient sceptical thinkers. But it is my contention that scepticism plays a special and different role in the period extending from the religious quarrels leading to the Reformation up to the development of modern metaphysical systems in the seventeenth century; a special and different role due to the fact that the intellectual crisis brought on by the Reformation coincided in time with the rediscovery and revival of the arguments of the ancient Greek sceptics. From the mid–fifteenth century onward, with the discovery of manuscripts of Sextus’ writings, there is a revival of interest and concern with ancient scepticism and with the application of its views to the problems of the day.
The selection of Savonarola as the starting point of this study is because he was the first to suggest that Greek sceptical materials should be published in Latin as part of the defense of true religion. A couple of decades later, Erasmus introduced other sceptical themes as a way of dealing with Luther’s challenge.
The stress in this study on the revival of interest and concern with the texts of Sextus Empiricus is not intended to minimize or ignore the collateral role played by such ancient authors as Diogenes Laertius or Cicero in bringing the classical sceptical views to the attention of sixteenth- and seventeenth-century thinkers. However, the writings of Sextus seem to have played a special and predominant role for many of the philosophers, theologians, and scientists considered here, and Sextus appears to have been the direct or indirect source of many of their arguments, concepts, and theories. It is only in the works of Sextus that a full presentation of the position of the Pyrrhonian sceptics appears, with all of their dialectical weapons employed against so many philosophical theories. Neither the presentations of Academic scepticism in Cicero and St. Augustine nor the summaries of both types of scepticism—Academic and Pyrrhonian—in Diogenes Laertius were rich enough to satisfy those concerned with the sceptical crisis of the Renaissance and Reformation. Hence thinkers like Michel Montaigne, Marin Mersenne, and Pierre Gassendi turned to Sextus for materials to use in dealing with the issues of their age. And hence the crisis is more aptly described as a crise pyrrhonienne than as a crise academicienne. By the end of the seventeenth century, the great sceptic Pierre Bayle could look back and see the reintroduction of the arguments of Sextus as the beginning of modern philosophy. Most writers of the period under consideration use the term “sceptic” as equivalent to “Pyrrhonian” and often follow Sextus’ view that the Academic sceptics were not really sceptics but actually were negative dogmatists. (In this connection it is noteworthy that the late seventeenth-century sceptic, Simon Foucher, took it upon himself to revive Academic scepticism and to try to defend it against such charges.)
The period of the history of scepticism considered in this book goes up to Pierre Bayle’s sceptical challenge to theories old and new in philosophy, science, and theology. He covers Descartes’ monumental attempt to answer scepticism and the reworking of sceptical challenges to deal with Descartes’ presentation. Spinoza, extending some of Descartes’ arguments to religion, then developed a new form of scepticism that was to flower in the Enlightenment. John Locke, Nicolas Malebranche, and Gottfried Wilhelm von Leibniz, each in their own way, sought to deal with scepticism as a living issue, especially as it appeared in the works of the late seventeenth-century sceptics Simon Foucher, Pierre-Daniel Huet, and Bayle. Voltaire later said that Bayle had provided the arsenal of the Enlightenment. What happens in the eighteenth century has been dealt with in many studies.
When I wrote the original preface to this work over forty years ago, I foresaw writing a series of studies on the history of the subsequent course of epistemological scepticism covering the major thinkers who play a role in this development from Spinoza to Hume to Kant to Kierkegaard. Much of this material has been examined in studies by myself, my students, and others. So I am not sure how necessary such volumes may be. My own interest has moved toward studying the history of irreligious scepticism. I have followed this with a book on Issac La Peyrére and his influence and other studies on millenarianism and messianism in relation to scepticism.
In this study, two key terms will be “scepticism” and “fideism,” and I should like to offer a preliminary indication as to how these will be understood in the context of this work. Since the term “scepticism” has been associated in the last two centuries with disbelief, especially disbelief of the central doctrines of the Judeo-Christian tradition, it may seem strange at first to read that the sceptics of the sixteenth and seventeenth centuries asserted, almost unanimously, that they were sincere believers in the Christian religion. Whether they were or not will be considered later. But the acceptance of certain beliefs would not in itself contradict their alleged scepticism—scepticism meaning a philosophical view that raises doubts about the adequacy or reliability of the evidence that could be offered to justify any proposition. The sceptic, in either the Pyrrhonian or Academic tradition, developed arguments to show or suggest that the evidence, reasons, or proofs employed as grounds for our various beliefs were not completely satisfactory. Then the sceptics recommended suspense of judgment on the question of whether these beliefs were true. One might, however, still maintain the beliefs, even though all sorts of persuasive factors should not be mistaken for adequate evidence that the belief was true.
Hence “sceptic” and “believer” are not opposing classifications. The sceptic is raising doubts about the rational or evidential merits of the justifications given for a belief; he doubts that necessary and sufficient reasons either have been or could be discovered to show that any particular belief must be true and cannot possibly be false. But the sceptic may, like anyone else, still accept various beliefs.
Those whom I classify as fideists are persons who are sceptics with regard to the possibility of our attaining knowledge by rational means, without our possessing some basic truths known by faith (i.e., truths based on no rational evidence whatsoever). Thus, for example, the fideist might deny or doubt that necessary and sufficient reasons can be offered to establish the truth of the proposition “God exists,” and yet the fideist might say that the proposition could be known to be true only if one possessed some information through faith or if one believed certain things. Many of the thinkers whom I would classify as fideists held that either there are persuasive factors that can induce belief, but not prove or establish the truth of what is believed, or that after one has found or accepted one’s faith, reasons can be offered that explain or clarify what one believes without proving or establishing it.
Fideism covers a group of possible views, extending from (1) that of blind faith, which denies to reason any capacity whatsoever to reach the truth, or to make it plausible, and which bases all certitude on a complete and unquestioning adherence to some revealed or accepted truths, to (2) that of making faith prior to reason. The latter view denies to reason any complete and absolute certitude of the truth prior to the acceptance of some proposition or propositions by faith (i.e., admitting that all rational propositions are to some degree doubtful prior to accepting something on faith), even though reason may play some relative or probable role in the search for, or explanation of, the truth. In these possible versions of fideism, there is, it seems to me, a common core, namely that knowledge, considered as information about the world that cannot possibly be false, is unattainable without accepting something on faith and that, independent of faith, sceptical doubts can be raised about any alleged knowledge claims. Some thinkers, Bayle and Kierkegaard for example, have pressed the faith element and have insisted that there can be no relation between what is accepted on faith and any evidence or reasons that can be given for the articles of faith. Bayle’s erstwhile colleague and later enemy Pierre Jurieu summed this up by asserting, “Je le crois parce que je veux le croire.” No further reasons are demanded or sought, and what is accepted on faith may be at variance with what is reasonable or even demonstrable. On the other hand, thinkers such as St. Augustine and many of the Augustinians have insisted that reasons can be given for faith, after one has accepted it, and that reasons that may induce belief can be given prior to the acceptance of the faith but do not demonstrate the truth of what is believed. Both the Augustinian and the Kierkegaardian views I class as fideistic, in that they both recognize that no indubitable truths can be found or established without some element of faith, whether religious, metaphysical, or something else.
The usage that I am employing corresponds, I believe, to that of many Protestant writers when they classify St. Augustine, Luther, Calvin, Pascal, and Kierkegaard together as fideists. Some Catholic writers, like my good friend the late Father Julien-Eymard d’Angers, feel that the term “fideist” should be restricted to those who deny reason any role or function in the search for truth, both before and after the acceptance of faith. In this sense, St. Augustine and perhaps Pascal (and some interpreters would argue, perhaps Luther, Calvin, and even Kierkegaard) would no longer be classified as fideists.
The decision as to how to define the word “fideism” is partly terminological and partly doctrinal. The word can obviously be defined in various ways to correspond to various usages. But also involved in the decision as to what the term means is a basic distinction between Reformation Protestant thought and that of Roman Catholicism, since Roman Catholicism has condemned fideism as a heresy and has found it a basic fault of Protestantism, while the nonliberal Protestants have contended that fideism is a basic element of fundamental Christianity and an element that occurs in the teachings of St. Paul and St. Augustine. Though my usage corresponds more to that of Protestant writers than that of Catholic ones, I do not thereby intend to prejudge the issues in dispute or to take one side rather than the other.
In employing the meaning of “fideism” that I do, I have followed what is a fairly common usage in the literature in English. Further, I think that this usage brings out more clearly the sceptical element that is involved in the fideistic view, broadly conceived. However, it is obvious that if the classifications “sceptic” and “fideist” were differently defined then various figures whom I so classify might be categorized in a quite different way.
The antithesis of scepticism, in this study, is “dogmatism,” the view that evidence can be offered to establish that at least one nonempirical proposition cannot possibly be false. Like the sceptics who will be considered here, I believe that doubts can be cast on any such dogmatic claims and that such claims ultimately rest on some element of faith rather than evidence. If this is so, any dogmatic view becomes to some degree fideistic. However, if this could be demonstrated, then the sceptic would be sure of something and would become a dogmatist.
My sympathies are on the side of the sceptics I have been studying. But in showing how certain elements of their views led to the type of scepticism held by Hume it is not my intention to advocate this particular result of the development of the nouveau pyrrhonisme. As a matter of fact, I am more in sympathy with those who used the sceptical and fideistic views of the nouveaux pyrrhoniens for religious rather than secular purposes, and I have tried to bring this out in other studies.
My approach is that of the history of ideas as developed in many recent studies. I was influenced from my college days onward by people such as Alexandre Koyré, John Herman Randall, Paul Oskar Kristeller, and many others. I have taken various elements of their methodologies to use to examine writers who speak about scepticism from Savonarola onward. Some have suggested that I am not always speaking about scepticism but rather about people who discuss scepticism. This may be the case, but I do not know how one could write a history of scepticism without it being mainly about the people who discuss the subject. I have also been accused of minimizing the social, political, and cultural background in which the sceptics were operating. I have tried to profit from many of these kinds of studies and incorporate material from them. There is, of course, much more to be done in placing the thinker in his or her milieu. Many discussions of the authors I include concentrate principally on the ideas of the person independent of circumstances. This, I feel, can be misleading unless one takes into account what various ideas and arguments were represented at various times in history. Striking an appropriate balance between intellectual history and cultural history is extremely difficult, and I have done my best with my resources. I trust others will go on exploring sceptical currents and enrich our understanding of the role scepticism played in bringing about our present intellectual world.
A couple of years ago when I started considering what ought to be done to prepare a new edition in light of all the research that had been done by scholars in the United States and Europe in the last two decades, I pondered several possibilities. One was just to leave the text as is, except for correcting obvious errors and appending a forward dealing with the material about Savonarola and his group and a concluding essay about scepticism after Spinoza. This would have been joined with a bibliographical essay about what had been written in the last twenty years. When I considered this, it seemed that the original book would look a bit disjointed unless it was also brought up to date and supplemented where significant new material had been found. So, about a year and a half ago, I started on the revision with the aid and comfort of two excellent assistants, Stephanie Chasin and Gabriella Goldstein. A complicating factor was that by the time I started on the revision I could no longer read texts, and so the job involved lots of optical and scanning devices and special computer programs, as well as laborious reading by my assistants. I was also no longer able to use libraries and had to rely on assistants to get materials for me and on colleagues all over the planet to send me material or look things up. I have tried to acknowledge the many, many people who have helped on this, and I hope that the results were worth their efforts.