Glanvill, Joseph (1636–1680)
Joseph Glanvill was a skeptic, a prominent defender of the experimental research of the early Royal Society, a liberal rationalistic Anglican theologian and preacher, and a staunch and influential believer in witchcraft. He studied at Cambridge, where he came under the influence of Henry More. On first learning of René Descartes's work Glanvill became an advocate of Cartesianism but was quickly led to cast doubt on it as a metaphysical theory because of More's objections. He then treated Cartesianism as a working hypothesis and began analyzing how much certitude anyone could have about what is going on in the world. He came into contact with John Wilkins, the bishop of Chester, and began developing his case in terms of the categories employed by him.
Glanvill's first work, The Vanity of Dogmatizing (1661), was soon revised into the larger Scepsis Scientifica (1665), and began with a most laudatory "Address to the Royal Society," which led to Glanvill being elected as a fellow.
Glanvill and Skepticism
Glanvill saw the skeptical problem as one that could not be so easily set aside. He saw the reliability of one's faculties as central for avoiding any ultimate and overwhelming skepticism. But Glanvill saw that the kind of certainty one would need to be absolutely sure of one's faculties ("infallible certainty," in which one is assured, "'tis impossible things should be otherwise than we conceive them or affirm them") is unattainable—"for it may not be absolutely impossible, but that our Faculties may be so construed, as always to deceive us in the things we judg most certain and assured."
One may not be able to attain infallible certitude, but one can attain indubitable certitude that one's faculties are true. This is indubitable in two senses: first, that one finds that one has to believe them, and, second, that one has no reason or cause for doubting them. One has to believe one's faculties are reliable if one is to have any rational life at all, even though one has no evidence that one's faculties are, in fact, reliable.
Glanvill carried this on to base acceptance of historical data (and especially that of scripture) on the indubitable principle that "Mankind cannot be supposed to combine to deceive, in things wherein they can have no design or interest to do it." So, skepticism can be set aside in mathematics, science, history, and theology, because one has no actual reason to doubt the results in these areas. One has to believe various findings and act with confidence. But, having said this, Glanvill immediately made clear that he had not offered or provided any way of eliminating ultimate skepticism.
For Glanvill, reasons for doubting had to be reasonable. Descartes's reasons for doubting he dismissed as hyperbolic or metaphysical. No reasonable person would entertain them. On the contrary, there can be reasonable doubts about many things, but this does not prevent one from having a degree of certitude about other matters. Glanvill insisted that human beings are basically in a state of ignorance due to the original Fall. They cannot know the springs and principles by which the world is operating. They can only hypothesize about this and recognize that any hypothesis could be false. There is a reasonable basis for doubting in that one never has sufficient evidence or knowledge and one cannot be sure that things cannot be otherwise than one conceives them.
Glanvill introduced what was to be an important point in later scientific thought, namely, that one can never find necessary connections between events. Any causal hypothesis that one works out is always open to question and doubt, since one does not understand the inner workings of Nature. One can find concomitances of events (what David Hume later called constant conjunctions) but not necessary connections. Because of this analysis of one's causal reason, Glanvill has often been considered a precursor of Hume, although there is no evidence that Hume ever read any of his work.
Reason and Religion
Glanvill's discussion of the relation of reason and religion is perhaps his most original contribution—that of offering a rational-skeptical fideism as a way of living with irremediable skepticism. Glanvill made the acceptance of the reliability of one's faculties a genuine act of faith. "The belief of our Reason is an Exercise of Faith, and Faith is an Act of Reason." He had preceded this by stating that "Reason is certain and infallible," which turns out to be based on one's knowledge "that first Principles are certain, and that our Senses do not deceive us, because God that bestowed them upon us, is True and Good."
Glanvill was not emulating Descartes in making true knowledge depend on the proof that God is not a deceiver. Rather, Glanvill was offering a kind of rational fideism. Faith, and faith alone, is the basis for one's belief in reason. One believes in reason because one believes in God's veracity. One does not try to prove that God is truthful; one believes this. Thus, faith in God gives one faith in reason, which in turn "justifies" one's belief that God is no deceiver.
Glanvill saw that the ultimate guarantee of one's certitude depends not on what one can prove, but on what one can believe. One can believe that God is truthful, and hence believe in the reliability of one's faculties. The first belief is reasonable, since one has no reason to doubt of it. This, then, enables one to avoid ultimate skepticism, by avoiding the fundamental skeptical problem of proving one's first principles.
Glanvill's rational fideism grows out of seeing the conditions requisite for certain and unquestionable reasoning (namely, that God is reliable), and is in sharp contrast to the irrational fideism being offered in the late seventeenth century by Pierre Bayle and Pierre Jurieu. Glanvill posed the possibility that rationality could be based on faith, and in terms of what human beings consider reasonable, accepting such faith is an exercise of reason. Using this rational fideism, Glanvill tried to show the reasonableness of religious belief and of Latitudinarian Christianity.
Glanvill provided an epistemology for a "mitigated" skepticism, which could delineate the kind of certitude that the new scientists could find. Instead of basing the "new science" on dogmatic metaphysical principles, he offered an undogmatic semiskepticism sufficient to encourage the nondogmatic inquiries of the scientists of the Royal Society, while opposing the dogmatism of Descartes, Thomas Hobbes, and Benedict (Baruch) de Spinoza.
Glanvill's belief in witches comes from his critique of the materialism of Hobbes and others. The question of whether evil spirits exist, Glanvill pointed out, is a factual question, not a metaphysical one and has to be answered by examining the empirical evidence. Glanvill compiled ample testimonials to convince any "reasonable" person that (1) it is possible that evil spirits or witches exist, (2) it is probable that they do, and (3) that the acknowledgment of their existence allows for the best explanation of various observed phenomena. Glanvill pointed out that various societies have laws against practicing witchcraft, so it seems likely that there is something of this sort that could be practiced. The possible existence of witches is also part of a larger and more significant question—that of the existence of spirits. If demonic or evil spirits cannot exist, then how can one be sure that good spirits—angels or God—can exist? To deny the possibility of the existence of witches is to deny the possibility of any sort of spiritual or divine world.
Glanvill offered a nondogmatic, or deontologized, Cartesianism as the best scientific model of explanation for natural phenomena. In his continuation of Francis Bacon's New Atlantis Glanvill had his sage present Cartesianism as "the neatest Mechanical System of things that had appear'd in the world," though it was not certain or all encompassing. The sages could also accept the preexistence of the soul and the existence of spiritual agents, whose manner of operating may not be known or even knowable to one.
Glanvill was an eclectic philosopher, taking his views in part from More, Descartes, Bacon, Anne Conway, and the members of the Royal Society. Glanvill's world of natural science, spirits, and Christianity, based on the "plausible" testimony of historical documents, is one way these kinds of knowledge could be brought into harmony. Glanvill paid the price of having this all rest on a basically ineliminable skepticism. If one could find solace and comfort in a faith in a nondeceiving Deity, then a nice, harmonious world of science and religion could be accepted.
works by glanvill
The Vanity of Dogmatizing. London: Printed by E. C. for H. Eversden, 1661.
Scepsis Scientifica. London: Printed by E. Cotes for H. Eversden, 1665.
A Philosophical Endeavor in the Defense of the Being of Witches and Apparitions. London: Printed by E. Cotes for James Collins, 1668a.
Plus Ultra: or, the Progress and Advancement of Knowledge Since the Days of Aristotle. London: Printed for J. Collins, 1668b.
Essays on Several Important Subjects in Philosophy and Religion. London: Printed by J. D. for J. Baker, 1676.
works about glanvill
Cope, Jackson I. Joseph Glanvill, Anglican Apologist. St. Louis, MO: Committee on Publications, Washington University, 1956.
Popkin, Richard H. "The Development of the Philosophical Reputation of Joseph Glanvill." Journal of the History of Ideas 15 (1954): 305–311.
Popkin, Richard H. "Joseph Glanvill: Precursor of Hume." Journal of the History of Ideas 14 (1953): 292–303.
Talmor, Sascha. Glanvill: The Uses and Abuses of Scepticism. Oxford, U.K.: Pergamon Press, 1981.
Van Leeuwen, Henry G. The Problem of Certainty in English Thought, 1630–1690. The Hague: Nijhoff, 1963.
Richard H. Popkin (1967, 2005)