Hume's Abject Failure, The Argument Against Miracles John Earman, Professor of the History and Philosophy of Science, University of Pittsburgh Abstract : Hume's famous essay on miracles is set in the context of the larger debate that was taking place in the eighteenth century about the nature of miracles and the ability of eyewitness testimony to establish the credibility of such events. The author contents that Hume's argument against miracles is largely unoriginal and chiefly without merit where it is original. To advance the issues so provocatively posed by Hume's essay requires the tools of the probability calculus being developed by Hume's contemporaries but largely ignored by Hume. Content Part I Hume on Miracles 1. Abstract 1 2 Hume's Religious Orientation 4 3 The Origins of Hume's Essay 6 4 The Puzzles of Hume's Definitions of “Miracles” 8 5 Conceptions of Miracles 9 6 What a Miracle Is for Hume 12 7 The Eighteenth-Century Debate on Miracles 14 8 The Structure of Hume's Essay 20 9 Hume's Straight Rule of Induction and His “Proof” Against Miracles 22 10 Hume, Bayes, and Price 24 11 Bayes and Bayesianism 26 12 The Bayes-Price Rejection of Hume's Straight Rule 29 13 Hume's Stultification of Scientific Inquiry 31 14 The Indian Prince 33 15 Hume's Maxim 38 16 What Is Hume's Thesis? 43 17 Hume's Diminution Principle 49 18 Multiple Witnessing 53 19 More Multiple Witnessing 56 20 What Is Right About Hume's Position 59 21 Fall Back Positions for Hume 61 22 Probabilifying Religious Doctrines 65 23 Hume's Contrary Miracles Argument 67 24 Conclusion 70 Appendix on Probability 75 Works Cited 87 Additional Bibliography 93 Part II The Documents 96 John Locke, an Essay Concerning Human Understanding (1690), Book IV, Chapters 15 and 16 97 Benedict De Spinoza, a Theologico-Political Treatise (1670), Chapter 6 107 John Locke, “A Discourse of Miracles” (1706) 114 Thomas Sherlock, the Tryal of the Witnesses of the Resurrection of Jesus (11th Ed., 1729) 125 David Hume, Enquiry Concerning Human Understanding (1777), Section 10, “Of Miracles” 140 Richard Price, Four Dissertations (2D Ed. 1768), Dissertation IV, “On the Importance of Christianity and the Nature of Historical Evidence, and Miracles”. 157 George Campbell, a Dissertation on Miracles (1762) 176 Anonymous (George Hooper?), “A Calculation of the Credibility of Human Testimony” (1699) 193 Pierre Simon Laplace, a Philosophical Essay on Probability (1814), Chapter 11 “Concerning the Probabilities of Testimonies” 194 Charles Babbage, Ninth Bridgewater Treatise (2D Ed. 1838), Chapter 10, “On Hume's Argument Against Miracles” 203 Preface An impressive amount of ink has been spilt over Hume's “Of Miracles.” It is almost universally assumed, by Hume's admirers and critics alike, that “Of Miracles” offers a powerful and original argument against miracles. On the contrary, I contend that Hume's argument is largely derivative, almost wholly without merit where it is original, and worst of all, reveals the impoverishment of his treatment of inductive reasoning. Hume scholars will no doubt be enraged by this charge. Good! There has been much too much genuflecting at Hume's altar. If the only purpose of the present work were to bash “Of Miracles,” it would not be worth the candle. But in fact, Hume's essay does have the virtue of bringing into focus a number of central issues in induction, epistemology, and philosophy of religion. It is my contention, however, that a proper treatment of these issues requires the use of the probability calculus that was being developed by Hume's contemporaries but of which Hume was largely unaware. In Part I of this monograph. I provide a detailed critique of “Of Miracles” from the perspective of the version of this apparatus developed by Thomas Bayes and Richard Price (“Bayesianism”). Part II reproduces some not easily obtained early writings on the Bayesian analysis of eyewitness testimony. Also included are documents that set the historical context in which Hume was working; without this context, a fair evaluation of Hume's contribution is impossible. Readers will also want to consult Tweyman (1996) which reprints selections from tracts, from 1752– 1882, reacting to Hume's essay. The selections from primary texts in Part II are arranged as follows. The first selection, from Locke's Essay Concerning Human Understanding , sets the general problem of which miracles is a special case; namely, how is belief to be apportioned when uniform experience conflicts with eyewitness testimony? The next three selections from Spinoza, Locke, and Samuel Clarke illustrate the conflicting conceptions of miracles and their role in Christian apologetics that were extant in Hume's day. Next come selections from Thomas Sherlock and Peter Annet, which give some of the flavor and substance of the eighteenth-century miracles debate in Britain. This is followed by the text of Hume's “Of Miracles”; the changes that Hume made in various editions are recorded. Then come excerpts from two of the contemporary reactions to Hume's essay. The first, by George Campbell, is better known and rhetorically more forceful; the second, by Richard Price, though less well known and not as rhetorically successful, is more philosophically interesting and gave Hume greater pause. Finally, there are three selections, from Anonymous (George Hooper?), Laplace, and George Babbage, that illustrate attempts to use the probability calculus to quantify the effects of eyewitness testimony and, in particular, the effects of multiple witnessing in boosting credibility and the effects of error, self-deception, and deceit in diminishing credibility. Except where noted otherwise, the italics in the text is from the original author. I hope that the present work will be found useful by students in the history of philosophy, in epistemology, and in philosophy of religion. Toward this end, the bibliography contains a representative sample of references to recent literature on Hume's miracle argument. I have not attempted to respond to all of this literature— that would require a book in itself. Rather, I have attempted to present an analysis that, whatever its other merits and demerits, is self-contained and thematically unified. In criticizing Hume's argument against miracles. I have occasionally been subjected to a kind of reverse inquisition: since I attack Hume, must I not have some hidden agenda of Christian apologetics? I find such inquisitions profoundly distasteful since they deflect attention from the real issues. I am not averse, however, to laying my cards on the table. I find much that is valuable in the Judeo-Christian heritage, but I find nothing attractive, either intellectually or emotionally, in the theological doctrines of Christianity. If I had need of Gods, they would be the Gods of the Greeks and the Romans. The attack on Hume is motivated purely by a desire to set the record straight and frame the issues in a way that makes discussion of them more fruitful— but I must admit, after a bit of soul searching, that the sharpness of the attack is in part a reaction to what I see as pretentious sneering. I gratefully acknowledge the helpful comments on earlier drafts of my essay received from a number of people. If I tried to name them all I would be sure to insult some by forgetting them. But I would be remiss if I did not give special thanks to Richard Gale, Rodney Holder, Colin Howson, Philip and Patrica Kitcher, Noretta Koertge, Laura Ruetsche, David Schrader, and Teddy Seidenfeld. J.E. Pittsburgh, Pennsylvania March 2000 Part I Hume on Miracles John Earman Abstract : Part I contains the author's reconstruction and critical evaluation of Hume's argument against miracles. Especially emphasized is the utility of the probabilistic epistemology that emerges from the work of Hume's contemporaries, Thomas Bayes and Richard Price, for evaluating the evidential value of the testimony of fallible witnesses. Keywords: Bayes, Bayesianism, eyewitness testimony, Hume, miracles, Richard Price, probabilistic epistemology, probability Section X (“Of Miracles”) of Hume's Enquiry Concerning Human Understanding 1 is a failure. In philosophy, where almost all ambitious projects are failures, this may seem a mild criticism. So to be blunt. I contend that “Of Miracles” is an abject failure. It is not simply that Hume's essay does not achieve its goals, but that his goals are ambiguous and confused. Most of Hume's considerations are unoriginal, warmed over versions of arguments that are found in the writings of predecessors and contemporaries. And the parts of “Of Miracles” that set Hume apart do not stand up to scrutiny. Worse still, the essay reveals the weakness and the poverty of Hume's own account of induction and probabilistic reasoning. And to cap it all off, the essay represents the kind of overraching that gives philosophy a bad name. These charges will be detailed and supported below, but at the outset I want to elaborate on the last one. An apt analogy for Hume's project is the search for a “demarcation criterion.” As originally conceived by the logical positivists, such a criterion would separate genuine assertions having cognitive significance from meaningless gibberish. More recently, there has been a quest for a criterion to cleave genuine science from pseudo-science. The history of these twin quests has been a history of failure. 2 One of the morals to be drawn from a failure to find a litmus test of the pseudo-scientific is relevant here: namely, it does not much matter what label one sticks on a particular assertion or an enterprise; 3 the interesting questions are whether the assertion merits belief and whether the enterprise is conducive to producing well-founded belief.