Hume's Contrasting Views on Causality: Treatise vs. Enquiry, Slides of Philosophy

Download Hume's Contrasting Views on Causality: Treatise vs. Enquiry and more Slides Philosophy in PDF only on Docsity! Hume’s Considered View on Causality Lee Archie      ,  29649 Version 0.8 2005 Abstract Hume presents two definitions of cause in his Enquiry which correspond to his two definitions in his Treatise. The first of the definitions is ontological and the second is psychological; indeed, the definitions are extensionally and intensionally distinct. The critical mistake of the skeptical interpretation is the assumption that the two definitions are equivalent, and the critical mistake of the necessitarian is the assumption an association of ideas can be had from one experiment. This paper attempts to clarify Hume’s finally considered position of causality. 1 The Problem of Interpretation Before attending to the influential elements of Hume’s theory, it is worthwhile to indicate several reasons for the often disparate interpretations of causation drawn from A Treatise of Human Nature (1739),1 An Abstract of a Treatise of Human Na- ture(1740), and An Enquiry Concerning the Human Understanding (1758)2 The purpose of this section is to indicate that much of the psychological support for the causal argumentation in the Treatise is irrelevant to the influence of Hume’s doctrines; in this manner, Hume’s theory of causality can be extricated to some extent from his detailed psychological arguments without creating major misun- derstandings. Hume completely disavowed the Treatise and wrote in an advertisement to the Enquiry that the argument in the Treatise needed clarification and better expres- sion. He admits to “some negligences” in reasoning, and he requests that the work 1E. L. A. Selby-Bigge (1888; rpt. London: Oxford Univ. Press, 1968). Hereafter page refer- ences to A Treatise of Human Nature will be cited in the text as “T.” In quotations from this work spelling but not punctuation has been modernized. 2E. P. H. Nidditch, 3rd ed. (1777; rpt. London: Oxford Univ. Press, 1975). Hereafter page references to A Enquiry Concerning the Human Understanding will be cited in the text as “E.” In quotations from this work spelling but not punctuation has been modernized. 1 THE PROBLEM OF INTERPRETATION not be regarded further. In addition, the Abstract, published anonymously, is far too sketchy by itself to provide a focus for causal doctrines. It is, for the most part, a summary of the arguments given in the Treatise and was disowned also.3 Thus, if we were to take Hume at his word, only the Enquiry should be studied for his full causal doctrines; however, this is not usually done for the following reasons. Hume’s youthful enthusiasm and to some degree his perspicacity in the Trea- tise are attenuated in two significant ways in the Enquiry. First, causal doctrines are reformulated with an eye toward simplicity and clarity; second, some difficult and controversial subjects of the Treatise are dropped from the Enquiry. Nat- urally, this situation opens fertile territory for scholars. For example, are there insurmountable differences between the works?4 More specifically, is Hume’s retraction in the Enquiry to be taken seriously?5, p. 57, argues that Hume sim- ply wanted to dissociate himself from a badly received work. Some writers have taken Hume at his word and only considered the Enquiry; see, for example, An- thony Flew, Hume’s Philosophy of Belief New York: Humanities Press, 1961), pp. 1-17. Are the accounts of causation in both works consistent with one an- other?6 Is there a predominant doctrine of causality in the two works?7 There have been several different plausible responses to these questions, and because of this, Hume’s influence is manifold. More important for the present discussion, several critical problems arise from the omission of vital topics in the Enquiry–topics necessary for the completion of the causal argument. The ideas of existence, external existence, and substance, as well as the distinction between causation as a philosophical and a natural relation are omitted. Furthermore, the consideration of space and time is almost totally 3Charles Hendel, however, argues that the Abstract was an outline of the Enquiry rather than the Treatise. See his “Editor’s Introduction,” An Inquiry Concerning Human Understanding (In- dianapolis: Bobbs-Merrill, 1955), pp. xviii-li. J.O. Nelson suggests that the Abstract might have been written by Adam Smith. See his “Has the Authorship of the Abstract Really been Decided?,” Philosophical Quarterly, 26 (January, 1976), pp. 82-91. 4L. A. Selby-Bigge argues in the “Editor’s Introduction” to the Enquiry by means of a passage by passage comparison that the differences in the two works are significant, but there is not a substantial doctrinal difference. A survey of differences of opinion on this view point is illustrated by the following articles: W. B. Elkin, “Relation of the Treatise of Human Nature (Book I) to the Inquiry Concerning Human Understanding,” Philosophical Review, 3 (1894), pp. 672-688; J. O. Nelson, “Two Main Questions Concerning Hume’s Treatise and Enquiry,” Philosophical Review, 81 (1972), pp. 333-352; N. Kemp Smith, “David Hume: 1739-1939,” Aristotelian Society Proceedings, Suppl. Vol. 63 (1939), pp. i-xxiv. 5L. F. V. Kruse in Hume’s Philosophy in his Principal Work the Treatise, and in His Essays, trans. P. T. Federspiel (Oxford: Oxford Univ. Press, 1939 6J. O. Nelson in “Two Main Questions” convincingly argues that Hume disowned the Treatise because of its metaphysical arguments–an interpretation which this essay later adopts. 7In this chapter I assume without attempting to prove that the causal arguments in the Treatise and Enquiry are compatible; consequently, since both works have been influential, both are utilized in constructing Hume’s doctrines. For reasons given later, the causal arguments in the Enquiry are given more weight than is usually accorded by contemporary commentators. 2 1 THE PROBLEM OF INTERPRETATION Enquiry in the reconstruction of Hume’s doctrine of causation is to avoid the onto- logical problem of explicating the contiguity of an impression and an idea. Kemp Smith, among others, notes that a substantial reason for writing the Enquiry was that Hume was disturbed about his former account of impressions and ideas in the Treatise.16 Another contrast between the two works is that the boundaries of what can be known are somewhat extended in the Enquiry: “All reasonings concerning matter of fact seem to be founded on the relation of cause and effect. By means of that relation alone we can go beyond the evidence of our memory and senses” (E, 26, my italics). Hume states in the “Introduction” to the Enquiry that the handling of psychological questions are nearly sufficient in themselves to account for all of science: “It becomes, therefore, no inconsiderable part of science barely to know the different operations of mind, to separate them from each other, to class them under their proper heads ...” and so on. On the same page Hume refers to this enquiry as “mental geography, of the delineation of the distinct parts and powers of the mind” (E, 13). Then, using Newton’s natural philosophy as a methodolog- ical paradigm, he asks, “But may we not hope, that philosophy ... may carry its researches still farther, and discover, at least in some degree, the secret spring and principles, but which the human mind is actuated in its operations?” (E, 14). Since Newton had determined the laws and forces of the solar system, “there is no reason to despair of equal success in our enquiries concerning the mental powers and economy, if prosecuted with equal capacity and caution” (E, 14) In short, the Treatise’s construction of the science of man on narrowly circumscribed empirical foundations is broadened in the Enquiry: “To throw up at once all pretensions of this kind [i.e., going beyond the evidence of our senses to the establishment of general principles] may justly be deemed rash, precipitate, and dogmatical, than even the boldest and most affirmative philosophy, that has ever attempted to im- pose its crude dictates and principles on mankind” (E, 15). This contrast between the Treatise and Enquiry should not be pushed too far however, since Hume often maintained that the principles in both works are the same.17 16Kemp Smith, “David Hume,” p. xx. Cf., also Elkin, “Relation of the Treatise,” p. 682; Nelson, “Two Main Questions,” pp. 341-350; and Selby-Bigge, “Editor’s Introduction,” p. xii. Norman Melchert, “Hume’s Metaphysics,” Journal of Philosophy, 71 (1974), p. 753, suggests that the main source for these assessments is Hume’s own admission in the “Appendix” to the Treatise: “In short, there are two principles, which I cannot render consistent; nor is it in my power to renounce either of them; viz. that the mind never perceives any real connection among distinct existences” (T, 636, italics deleted). 17Phillip D. Cummins, “Hume’s Disavowal of the Treatise,” Philosophical Review, 82 (1973), pp. 371-379. Cummins attempts to establish that in both works Hume is committed to the position that psychological objects (impressions and ideas) are the subject matter of nonhumanistic science. I do not think that Cummins’ arguments are compelling, but I doubt that this dispute can be easily settled. I incline to the view that Hume of the Treatise was somewhat more dogmatic in many passages in his denial of unperceived objects. Hume mentions “the positive air which prevails in that book” (Grieg, Letters, Vol I. p. 187). In any case the procedural point, that Hume’s analysis 5 1 THE PROBLEM OF INTERPRETATION In addition, it is arguable that Hume might have been disturbed about an im- plication of the Treatise that all sciences are to be based on psychological ob- jects (impressions and ideas)–that “secret” causes and objects mentioned in the Treatise not only have no basis but are, in a straightforward sense, unknowable thing-in-themselves. In the Treatise Hume is constructing the science of man, not just according to “mental geography,” but according to the derivation of ideas and principles from impressions. The Enquiry, then, does not substantially alter Hume’s project of the science of man: the work is concerned with inference and belief as a basis for humanistic and physical sciences. Consequently, it, unlike the Treatise, does not base natural science on psychological entities. J. O. Nelson has plausibly argued that Hume’s repudiation of the Treatise was not unlike that of Wittgenstein’s rejection of the Tractatus. The major thrust of the Enquiry, according to Nelson is to criticize the flights of philosophical reasoning– in particularly, the theorizing from the nature of impression and ideas.18 He argues that in the Enquiry “that part of the science of man, which in the Treatise de- manded that the subject matter of the nonhumanistic sciences be shown to consist of psychological objects, is eliminated. This operation removes the metaphysical and therefore corrupt parts of the science of man but not the science of man.”19 The import of Nelson’s thesis for Hume’s doctrines of causality is adopted here without further argument as a convenient framework in which to study Hume’s contemporary influence. Therefore, Hume’s theory of causal inference in the Treatise and Enquiry is analyzed without an attempt to deal with the psychological basis for that kind of inference. These considerations provide some justification for ignoring much of the psy- chological and metaphysical bases for Hume’s conclusions about causal infer- ences. It is suggested that Hume may have rejected the Treatise for the following reasons. Hume was probably dissatisfied with psychological and metaphysical ar- guments concerning impression and ideas; he thought that he could establish his views on causation without supporting them by reference to psychological objects. Furthermore, he believed the Enquiry was a clearer statement of his philosophical principles. Certainly, the metaphysical support for Hume’s particular psycholog- ical doctrines in the Treatise have not been significant in many of the current interpretations of his causal doctrines. Speaking broadly, then, commentators are left with a retracted, complex, and somewhat inconsistent Treatise, a sketchier, less rigorous, but clearer Enquiry. For these reasons, it is not surprising Hume’s causal doctrines have been interpreted of causation can be studied independently of complex psychological support, seems to be agreed on all sides. Cummins writes, “The metaphysical doctrines of the Treatise were not repudiated; rather the detailed psychological arguments concerning the causes of beliefs were dropped” (p. 379). Also see footnote 16, p. 5. 18Elkin partially concurs: “the mode of expression is more hesitating and cautious than in the Treatise” (“Relation of the Treatise,” p. 682). 19Nelson, “Two Main Questions,” pp. 340-341. 6 2 HUME’S CAUSAL THEORY in different ways. The problems of collation are too many and too complex to be handled here, and if the rationale given for Hume’s rejection of the obscure psychological arguments of the Treatise are of any weight, it would be a mistake to count those arguments as essential to this theory of causality. Our interest is focused on Hume’s influential tenets of causality rather than a detailed analysis of the psychological support for those tenets. In this manner, those doctrines underlying what may be termed “the contemporary regularity theory” of causation are accented. 2 Hume’s Causal Theory Much of the controversy surrounding Hume’s analysis of causality stems from what his intentions are taken to be. Sterling Lamprecht points out that the sup- position that knowledge of the world begins from the knowledge of the struc- ture and function of the mind is an element in common among eighteenth cen- tury philosophical works. “It is this approach which created the epistemological problem with which modern philosophy has been so conspicuously concerned.”20 By means of a judicious selection of slightly guarded passages from the Treatise and Enquiry, different commentators have supposed the chief value of Hume’s method is predominately skeptical, logical, linguistic, empirical, or psychologi- cal.21 While it is true it is unwise to strike off the results of Hume’s causal anal- ysis from the methods of enquiry, it is equally unwise to select certain kinds of arguments from Hume’s causal analysis to fit one’s preconceptions of the kind of philosophy he was doing. One way to minimize the dangers of extracting Hume’s definitions of cause from the science of human nature is to organize the argu- mentation according to an ontological structure initially allowed but not finally endorsed by Hume: (1) external bodies, (2) perceptions, and (3) mind (cf., E, pp. 73-74, 82-83). By the organization of the examination of Hume’s two definitions in this way, the arrangement of this section will indirectly reflect Hume’s broader concerns of the science of man without attending explicitly to the Humean psy- chology and metaphysics. 20Sterling P. Lamprecht, “Empiricism and Epistemology in David Hume,” in Studies in the History of Ideas, Vol. 2, ed. Dept of Philosophy, Columbia University (New York: Columbia Univ. Press, 1925), pp. 221-222. 21For example, Hume’s influence is take mainly to be: (a) skeptical, by Rufus Suter, “A Skeptic Among the Scientists,” Scientific Monthly, 53 (1941), pp. 565-568; (b) logical, by Karl Aschen- brenner, “Psychologism in Hume,’ Philosophical Quarterly, 11 (1961), pp. 28-38; (c) linguistic, by Virgil C. Aldrich, “Two Hundred Years after Hume’s Treatise,” Journal of Philosophy, 36 (193(), pp. 600-609; (d) empirical, by R. E. Hobart, “Hume Without Scepticism (I),” Mind, 39 (1930), pp 273-301, and “Hume Without Scepticism (II),” Mind 39, pp. 409-425; and (e) psycho- logical, by James H. Lesher, ”Hume’s Analysis of ‘Cause’ and the ‘Two Definition’s Dispute’,” Journal of the History of Philosophy, 11 (1973), pp. 387-392. 7 4 THE TWO DEFINITIONS temological aspect), and the operations of mind (the psychological aspect). Hume only later concludes that the integrity of these perspectives cannot justifiably be maintained. 4 The Two Definitions The ontological and the epistemological approaches are reflected in Hume’s two definitions of cause in the Treatise: T-1: We may define a cause to be “An object precedent and contiguous to another, and where all the objects resembling the former are placed in like relations of precedency and contiguity to those objects, that resemble the latter” (T, 170). T-2: A cause is an object precedent and contiguous to another, and is so united with it, that the idea of the one determines the mind to form the idea of the other, and the impressions of the one to form a more lively idea of the other (T, 170). Obviously, the two definitions are quite different: indeed, the restated definitions in the Enquiry are different not only from each other but also from those given in the Treatise. The definitions from the Enquiry are set out for comparison: E-1: ... we may define cause to be ”An object, followed by another, and where all objects similar to the first are followed by objects similar to the second” or in other words ”where, if the first object had not been, the second never had existed” (E, 76). E-2: The appearance of a cause always conveys the mind by a customary transition, to the idea of the effect. Of this we have experience. We may, therefore suitable to this experience, form another definition of cause and call it ”An object followed by another, and whose appearance always con- veys the thought of the other” (E, 77). Although these definitions, together with the relevant textual support, are usually regarded as an expression of a regularity theory of causation, in fact several in- terpretations emerge from a consideration of Hume’s definitions. These interpre- tations are sometimes characterized as (1) the regularity theory, (2) the necessary connections theory, and (3) skepticism. Very little will be said concerning the latter two interpretations, and as will be argued later, they probably result from a confusion about Hume’s intentions. The first definitions, T-1 and E-1, hereafter termed ”the first textual defini- tions,” may be considered definitions from an ontological perspective. Neither the 10 4 THE TWO DEFINITIONS objects of the causal relation nor the causal relation itself are defined in terms of having been perceived.27 Also it seems apparent that no one could observe all instances of a given causal relation in the manner prescribed. In any case, even assuming that the requisite experiences could be had, definitions T-1 and E-1 do not require that instances must be observed in order for the causal relation to hold. Consequently, the first textual definitions are offered independently of causal be- liefs or inferences, although part of the definitions could be used in the analysis of causal beliefs or inferences. Apart from the epistemological question of how causal relations are known, the problem of the intelligibility of the first textual definitions in the Treatise and Enquiry remains to be considered. The first textual definitions are similar, but they are not, as come commentators have suggested, “unchanged.”28 In the Enquiry, the addition of “if the first object had not been, the second had never existed” suggests a counterfactual analysis. Even though the proper interpretation of coun- terfactual conditionals is troublesome, the two parts of the first textual definitions in the Enquiry clearly are not equivalent.29 The counterfactual, “If the first had not been, the second would not exist” does not follow from “The first is precedent and contiguous to the second, and all instances resembling the first are accompanied in this manner to instances resembling the second.” Normally, a counterfactual conditional does not imply that its antecedent is instantiated. Another difference between the first textual definitions of cause in the Treatise and Enquiry is that the use of “contiguity” and “precedence” in the first part of T-1 is expressed by the use of “following” in E-1. A succession of instances would have to be analyzable into contiguity and precedence of the first instance to the second for T-1 and E-1 to be equivalent. Tom L. Beauchamp gives such an ar- gument and concludes that “succession” means for Hume “non-contemporaneous but intervalless contiguity.”30 However, there is no need to insist on Beauchamp’s argument since Hume makes it fairly clear in the latter parts of the Treatise and in the Enquiry that spatial contiguity is not necessary for causality. For example, at one point Hume writes: 27The fact that the definition does not depend upon an observation leads some commentators to state that the ontological definition is the significant one. Cf., C. J. Ducasse, Nature, Mind and Death (La Salle: Open Court, 1951), p. 93; J. A. Robinson, ”Hume’s Two Definitions,” pp. 162-172. 28Robinson, “Hume’s Two Definitions,” p. 164. 29Sometimes the two parts of T-1, the regularity analysis and a counterfactual analysis, are taken to be Hume’s two definitions as in David Lewis, “Causation,” Journal of Philosophy, 70 (1973), pp. 556-557, but that use is not adopted here. 30Tom L. Beauchamp’s “Hume on Causation and Succession,” Dialogue, 13 (1974), p. 280. Monroe C. Beardsley points out that spatial contiguity was dropped as part of the analysis of causation in the Enquiry “because [Hume] was using the ‘event’ terminology in many places, and a consideration of the problems of contiguity with respect to events would have forced upon him a further analysis of the notion of event, and would thus have revealed some crucial difficulties in his argument” (“A Dilemma for Hume,” Philosophical Review, 52 (1943), p. 30). 11 4 THE TWO DEFINITIONS This maxim is that an object may exist, and yet be nowhere; and I assert, that this is not only possible, but that the greatest part of beings do and must exist after this manner. an object may be said to be nowhere, when its parts are not so situated with respect to each other, as to form any figure or quantity; nor the whole with respect to each other, as to form any figure or quantity; not the whole with respect to other bodies so as to answer to our notions of contiguity or distance. Now this is evidently the case with all our perceptions and objects, except those of sight and feeling (T, 235-236). Of course, on Hume’s view “our perceptions and objects” are causally related instances. Except in reference to the association of ideas, spatial contiguity is not men- tioned in the Enquiry, although Hume undoubtedly thought spatial contiguity im- portant for a denial of gravity acting at a distance (cf., E, 73 n). Since “All causes are of the same kind” (T, 171), namely efficient causes, if the spatial contiguity of objects is not a necessary condition for some objects being causally related, then it is not a necessary condition of causation. In Hume’s writings, objects subject to the causal relation include impressions, ideas, states of affairs, occurrences, events, and physical objects.31 Fundamen- tally, he presupposes that all these “objects” are traceable to simple impressions. The philosophical problems of resemblance and simplicity of the qualities of per- ceptions, together with the problem of individuation of simple impressions are formidable.32 In order to avoid plunging into the underlying metaphysical and psychological support for Hume’s doctrine of relations, the relatively neutral term “instance” is suggested as an adequate paraphrase of “object” in the definitions of cause. On the assumption that T-1 and E-1 are equivalent, then three conditions for individual instances c and e must be jointly satisfied for the causal relation to obtain. Df. 1: c causes e if and only if: (a) c is precedent to e on a specific occasion. (b) c is temporally contiguous to e on a specific occasion. (c) Instances resembling c are always precedent and temporally contigu- ous to instances resembling e. 31Beardsley notes: “In the Treatise [Hume] refers to causes and effects practically without ex- ception as ‘objects’ (or qualities of objects); in the Enquiry he retains this terminology during some phases of the discussion, but more often refers to causes and effects as ‘events’ ” (“A Dilemma for Hume” p. 28). 32R. J. Hawkins has carefully attempted to explicate these terms and render Hume’s account consistent, but he acknowledges “very large gaps in Hume’s system” (“Simplicity, Resemblance and Contrariety in Hume’s Treatise” Philosophical Quarterly, 26 (January, 1976), pp. 24-38). 12 4 THE TWO DEFINITIONS Realizing, therefore, that [the first textual definitions], omitting the element of inevitability or necessity, will shock those who believe, mistakenly, that it should be included therein, Hume offers in [the second textual definitions] a “compromise” characterization of the cause-effect relation ...38 Thus, the second textual definitions are an attempt to show how the first textual definitions may be applied to Hume’s more general interest of the science of man. Most writers since the time of J. A. Robinson’s article have recognized that the two kind of definitions are not equivalent. A typical account is given by Karl Ashenbrenner. He argues that in the first textual definitions Hume is giving a logical analysis for the purposes of science, and in the second textual definitions Hume is giving a psychological description of the process of causal inference.39 Of course, while Hume is aware that these two definitions are not identical, the regularity theorist is aware that to suggest that Hume was clear about the contem- porary distinction between psychology and philosophy is an anachronism.40 At the point in the Treatise where Hume takes up the two summarizing definitions, the text presupposes such a division of interest; however, later in the Treatise and in the Enquiry, the distinction between the two perspectives collapses. Hume writes in the “Appendix” to the Treatise: “If we carry our enquiry beyond the ap- pearances of objects to the senses, I am afraid, that most of our conclusions will be full of scepticism and uncertainty” (T, 639). Hume assumes that external physical objects, causes, and inductive inference cannot be practically doubted. for instance, he writes that “the utmost effort of hu- man reason is to reduce the principles, productive natural phenomena, to a greater simplicity, and to resolve the many particular effects into a few general causes, by means of reasoning from analogy, experience, and observation” (E, 30). Never- theless, the application of Hume’s radical empiricism41 shows that it is pointless to attempt to reason about the structure of the world apart from what can be known in human experience. Most of what Hume wrote on the subject of causation con- cerns the rejection of the theories which postulate hidden causes, necessary con- nections, and secret forces in nature. As is well known, Hume argues not only that necessary connection cannot be observed, as in the case of the collision of two billiard balls, but also that the supposition of power or energy is unwarranted (T, 91). We cannot “penetrate into the reason of the conjunction” (T, 93) between cause and effect. 38Robinson, “Hume’s Two Definitions,” p. 169. 39Aschenbrenner, “Psychologism,” pp. 28-31. 40J. A. Robinson rightly comments, “Systematic evasion of empirical questions is a affectation philosophers have acquired in the twentieth century, and it is a very silly one” (“Two Definitions of ‘Cause’ Reconsidered,” in Hume, ed. V. C. Chappell (Garden City: Doubleday, 1966), p. 163). 41William A. Wallace, Causality and Scientific Explanation, (Ann Arbor: Univ. of Michigan Press, 1974), Vol. 2, p. 41. 15 5 OTHER INTERPRETATIONS OF HUME’S DEFINITIONS 5 Other Interpretations of Hume’s Definitions It is uncontroversial that Hume denies that there are necessary connection in ob- jects independent of experience, but does he totally deny the idea of necessity from his account of causal inferences? There is not clear-cut answer to this ques- tion. The following quotation from the Enquiry states Hume’s position: “And as we can have no idea of anything which never appeared to our outward sense of inward sentiment, the necessary conclusion seems to be that we have no idea of connection or power at all, and that these words are absolutely with meaning, when employed either in philosophical reasoning or common life’ (E, 74). How- ever, Hume goes on to say, “But there still remains one method of avoiding this conclusion ...” (E, 74), and he proceeds to the two definitions of cause. Some passages from the Treatise suggest that “necessity” is part of the mean- ing of “cause.” Kemp Smith argues, “Two distinct factors are involved in the idea of necessary connexion, one as conditioning it, and one as constituting it Con- stancy of conjunction is requisite as that through which alone a custom or habit can be acquired.”42 It is undeniable that if Hume is attempting to justify causal inferences, then some kind of necessary connection must correspond to the mind’s determination in passing from one idea to another. However, as suggested earlier, this kind of interpretation is probably a misreading of Hume’s intentions. Many commentators have assumed that Hume regarded the two textual defini- tions in each work equivalent. Even if the first two conditions of both definitions, Df. 1 and Df. 2, are equivalent, it does not follow that the third condition of Df. 1 is equivalent to the third and fourth conditions of Df. 2; that is, D f .1(c) . D f .2(c)and(d). (2) However, if Df. 1 and Df. 2 were equivalent, the third and fourth conditions of Df. 2 suggest that Hume’s reasoning is a petitio principii.43 In the jargon adopted, on this view ontological causation is said to depend on the association of ideas; yet, at the same time, this view points out that according to Hume the association of ideas is only one kind of causation in general. When the circularity of the two textual definitions under this interpretation is considered with Hume’s destructive arguments against the ideas of necessary connection and power, Hume’s causal analysis is said to result in skepticism. However, probably the critical mistake of the skeptical interpretation of Hume’s definitions of cause is the assumption that the two definitions are equivalent. Others have pointed out Hume admits that one causal instance may be just as good as a thousand instances in the determination of causal relations. Hume 42Norman Kemp Smith, The Philosophy of David Hume (London: Macmillan, 1941), p. 373. For an extended comparison of the regularity theory with Kemp Smith’s view, see Gregory M. Zeigler, “Hume’s View of the Causal Relation,” Personalist, 56 (1975), pp. 351-263. 43For example, Bertrand Russell, A History of Western Philosophy (New York: Simon and Schuster, 1945), p. 667. 16 5 OTHER INTERPRETATIONS OF HUME’S DEFINITIONS indicates as much in the following: “we may obtain the knowledge of a particular cause merely by one experiment, provided it be made with judgment, and after a careful removal of all foreign and superfluous circumstances” (T, 104).44 Given the regularity interpretation, such a belief would be under very special circum- stances, for example, a “crucial” experiment. Wade L. Robison, among others concludes Hume’s admission is withdrawn in the Enquiry. Robison cites this text: “there appears not, throughout all nature, any one instance of connection which is conceivable by us” (E, 74)45 A careful reading of the Enquiry (esp. E, 73-74) in- dicates that in the context of the cited passage Hume is speaking about necessary connection. In general Hume held that sufficient past experiences of a relevant sort enable one to confirm a causal connection by one experiment, and repetitions of the experiment under similar condition will corroborate the causal judgment. He asserts in the Enquiry: It is only after a long course of uniform experiments in any kind, that we attain a firm reliance and security with regard to a particular event. Now where is that process of reasoning which, from one in- stance, draws a conclusion, so different from that which it infers from a hundred instances that are nowise different from that single one? This question I propose as much for the sake of information, as with an intention of raising difficulties. I cannot find, I cannot imagine any such reasoning (E, 36). Whether a causal connection can be known from only one observation and no prior observations of the relevant kind is quite doubtful on Hume’s theory. If there were only one possible instance of a causal connection, however, then by the first definition it would seem that c causes e. This causal relation could only be known by attending to “circumstances foreign to the cause” (E, 77). The Enquiry makes it quite clear that the basis on which “we form an inference from one [instance] to another,” is the assumption that nature is uniform: We have said that all arguments concerning existence are founded on the relation of cause and effect: that our knowledge of that rela- tion is derived entirely from experience; and that all our experimental conclusions proceed upon the supposition that the future will be con- formable to the past (E. 35). How is this supposition to be supported? A central difficulty with Hume’s theory is the justification for such judgments concerning matters of fact, and it is precisely this problem which prompted Kant’s answer to Hume. 44This passage refutes a possible counter-example given by Ducasse, Nature, Mind, and Death, p. 95. Also, cf., T, 173 ff. 45Robison, “Hume’s Ontological commitments,” p. 45n. 17