physics*1 Michael Moore seeks to elucidate the nature of causation and its role in ... 3 Moore, 2009d, 255-60; see Richard Wright, "Causation in Tort Law" 73 ...
1 2 Causation: Metaphysics or
Richard W.
Intuition?
Wright*
I. I n t r o d u c t i o n : C a u s a t i o n , Culpability, a n d R e s p o n s i b i l i t y In his magnum opus, Causation and Responsibility: An Essay in Law, Morals, and Metaphysics*1 Michael Moore seeks to elucidate the nature of causation and its role in determining moral and especially legal responsibility and blame. Following the lead of Herbert Hart and Tony Honore, 2 he claims that causation plays a pervasive and dominant role. Although he purports to disavow Hart and Honore's reliance on ordinary language usage as an indicator of actual causal relations,3 his frequent and often heavy reliance on supposed common intuitions to support his arguments 4 belies that disavowal. I agree with Moore that causation plays a major role in assessments of legal responsibility. However, I disagree with his account of the nature of and relationships among causation, responsibility, culpability, and blameworthiness, which, among other errors, reflects the frequent tendency among criminal law theorists to misunderstand tort law as being concerned, like criminal law, with culpability and blameworthiness. My initial idea in writing this chapter was to address those issues. However, trying to sort out and address all of the complex and often inconsistent strands in Moore's arguments proved too difficult to accomplish in the available time and allotted space. So I have instead picked up the strands of my ongoing debates with Moore regarding the nature of causation per se, in particular his criticism of my NESS (necessary element of a sufficient 5et) account and his espousal of an "I know it when I see it" primitivist singularist theory. II. T h e N E S S A c c o u n t According to the NESS account as initially elaborated, a condition c was a cause of a consequence e if and only if it was necessary for the sufficiency of a set of existing
* Copyright 2015 Richard W. Wright. Permission is hereby granted to copy for noncommercial purposes as long as appropriate citation is made to this publication. 1 Moore, 2009d. 2 H. L. A. Hart and A. M. HononJ, Causation in the Law (Oxford: Oxford University Press, 1959). 3 Moore, 2009d, 255-60; see Richard Wright, "Causation in Tort Law" 73 California Law Review 1735 (1985), 1788-803; Richard Wright, "The Nightmare and the Noble Dream: Causation and Responsibility," in Matthew Kramer et al. (eds.), The Legacy qfH. L, A. Hart: Legal, Political and Moral Philosophy (Oxford: Oxford University Press, 2008), 165. 4 E.g., Moore, 2009d, x-xii, 29-33,38-9,55-8,66,347,445-7,507.
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antecedent conditions that was sufficient for the occurrence of e.5 Subsequently, after recognizing that the necessity aspect of the NESS criterion need only be incorporated in the definition of a causal law, I recast the test for singular instances of causation as follows: an actual condition c was a cause of an actual condition e if and only if c was a part of (rather than being necessary for) the instantiation of one of the abstract conditions in the completely instantiated antecedent of a causal law, the consequent of which was instantiated by e immediately after the complete instantiation of its antecedent, or (as is more often the case) if c is connected to e through a sequence of such instantiations of causal laws.6 This test for singular causes obviously puts great weight on the definition of a causal law. Recently, I have tightened up my past descriptions of what constitutes a causal law, although the core idea remains the same: A causal law is an empirically derived statement that describes a successional relation between a set of abstract conditions (properties or features of possible events and states of affairs in our real world) that constitute the antecedent and one or more specified conditions of a distinct abstract event or state of affairs that constitute the consequent such that, regardless of the state of any other conditions, the instantiation of all the conditions in the antecedent entails the immediate instantiation of the consequent, which would not be entailed if less than all of the conditions in the antecedent were instantiated.7 I use the phrase "causal sufficiency" to refer to the requirement in the above definition of a causal law that all of the conditions in the antecedent of the causal law must be instantiated on the particular occasion. This complete instantiation requirement is critical and distinguishes the required sense of sufficiency in a causal law from mere lawful sufficiency, in the sense of a guarantee of the occurrence of the relevant consequence, which Moore refers to as "nomic sufficiency."8 Contrary to Moore's assumption 9 —which unfortunately is shared by many—guaranteeing the occurrence of some result is not the same as causing that result 1 0 Our knowledge of causal laws generally is incomplete. Even if it were complete, we rarely refer to completely specified causal laws, since such complete specification would 5 This definition was a clarification of my initial description of a NESS condition as a necessary clement of a sufficient set, which was ambiguous and thus failed to clearly incorporate the requirement, which has always been stated in my elaborations of the NESS account, that a NESS condition must be necessary for the sufficiency of the sufficient set See e.g., Wright, "Causation in Tort Law," 1790; Richard Wright, "Causation, Responsibility, Risk, Probability, Naked Statistics, and Proof: Pruning the Bramble Bush by Clarifying the Concepts" ["Pruning the Bramble Bush"), 73 Iowa Law Review 1001 (1988), 1019,1021,1041. For the history and defense of a similar account, developed independently a few years earlier by Ingeborg Puppe, which makes almost all of the points that I make in this chapter, often better than me, see Ingeborg Puppe, "The Concept of Causation in the Law," in Benedikt Kahmen and Markus Stepanians (eds.), Critical Essays on "Causation and Responsibility" (Berlin: De Gruyter, 2013), 67 [Kahmen and Stepanians, Critical Essays]. 6 Richard Wright, "Acts and Omissions as Positive and Negative Causes" ["Acts and Omissions"], in Jason W. Neyers et al. (eds.), Emerging Issues in Tort Law (Oxford: Hart, 2007), 297-8; Wright, "Pruning the Bramble Bush," 1045. 7 Richard Wright, "The NESS Account of Natural Causation: A Response to Criticisms" ["NESS Account"], in Richard Goldberg (ed.), Perspectives on Causation (Oxford: Hart, 2011), 289; cf e.g., Wright, "Acts and Omissions," 293-4 and n. 18-therein. 8 9 Moore, 2009d, 475. Moore, 2009d, 474. 10 Wright, "Acts and Omissions," 298-300; see section III.D of this chapter.
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be extremely burdensome and unnecessarily detailed and lengthy. We rather employ causal generalizations, which refer to only some of the antecedent conditions in the relevant causal laws and have only as much specificity as is possible and needed in the particular situation. However, when we make an assertion regarding a singular instance of causation, we are implicitly asserting that all the unstated as well as the stated conditions in the relevant causal generalizations and all the unknown as-well as known conditions in the causal laws underlying the causal generalizations were instantiated on the particular occasion. Even when the inference of an applicable causal generalization (and the underlying causal laws) is based on a single observation of a singular instance of causation, the inference of causation in the singular instance comes after and depends upon the inference of the applicable causal generalization. In such instances the order is: (1) observation of the occurrence, (2) inference of the causal generalization based on the observation, and (3) assertion of causation through enunciation of the singular causal statement, which implicitly invokes the causal generalization. III. A l l e g e d D e f i c i e n c i e s o f t h e N E S S A c c o u n t A, Definitional issues Moore claims that the NESS account is "viciously*circular,M since causal terminology is often used in its elaboration and it relies upon the concept of causal laws.11 However, one need merely look at the definition of a causal law in section II of this chapter, as well as the definitions in my prior work,12 to see that, whatever other flaws they may have, they do not contain any causal language or suppositions. Similarly, the concept of causal sufficiency is defined non-circularly as the complete instantiation of all the conditions in the antecedent of a causal law (the definition of which contains no causal language or suppositions and thus could be substituted for "causal law" to produce a definition of causal sufficiency that contains no causal language), or, alternatively, as the label for that aspect of the non-circularly defined causal law. There is no conceptual circularity here, vicious or otherwise. Moore complains that my definition of a causal law, which requires that it be "an empirically derived statement that describes a successional relation between... distinct abstract event[s] or state[s] of affairs," excludes merely analytic, logical, identity, or mereological (part to its whole) relations. Although he and everyone else agrees that these are not causal relations and should be excluded,13 he declares that my defining a causal law so as to exclude them, while not circular, is "ad hoc in that it is unmotivated by the nature being attributed to causation."14 Really?! B. Causal directionality Under a mere nomic (lawful) sufficiency conception of causation, which fails to encompass causal directionality, consequents can be treated as causes of one of their antecedent conditions by simply inverting the relevant law. For example, we could treat 11 15
12 Moore, 2009d, 477,484,494-5. E.g., Wright, "Acts and Omissions," 293-4 and n. 18. 14 See Wright, "NESS Account," 286, n. 9. Moore, 2013b, 331,336; see Moore, 2009d, 477.
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the shadow cast by a flagpole as a cause of the flagpole's height, since, given the shadow, the laws of geometry, and all the conditions in the antecedent of the law for casting shadows other than the flagpole's height, including the location of the sun, we can infer the height, 15 However, if the relevant law has directionality, that is, is a causal law as I have defined it, this maneuver is blocked. Through experience and/or education, we know that the relevant causal law has the height of the flagpole as one of the conditions in the antecedent of the causal law and the shadow as the consequent. In his most recent criticism of the NESS account, after initially accusing me of "particularly blatant" circularity for "attempt [ing] to smuggle the asymmetricality and time-directionality of causation into his notion of [causal] sufficiency,"16 Moore retreats to an assertion of ad hoc, unmotivated stipulation similar to the one that he made regarding my defining causal laws so as to exclude analytical and mereological relations. Noting my inclusion of the terms "successive relation" and "immediate" in my definition of a causal law, he states: [A] symmetricality and temporal order ("successive relation," "immediate") are merely stipulative add-ons to nomic sufficiency that in no way follow from the supposed nature of causation (viz, nomic sufficiency). Sure, causation is an asymmetrical and time-ordered relation, and nomic sufficiency as such is not. But causal sufficiency has these features—once one by fiat adds these features of causation to nomic sufficiency One can fairly demand . . . that [Wright] show us how an asymmetric and time-ordered relation (causation) can be identified as a seemingly different relation (nomic sufficiency...) that is neither.17 Either Moore doesn't get it, or he refuses to accept it. From the beginning my effort has been to provide an account of causation, and from the beginning it was clear to me, as it is to Moore, that simple nomic (lawful) sufficiency does not fully capture the concept of causation, for all the reasons that Moore explains, which I also have elaborated in my work. I have emphasized the necessity of developing and employing a conception of causal laws and of the sufficiency employed in them that is distinct from mere lawful sufficiency, which, in order to flag the distinction, I call causal sufficiency. Moore commends John Mackie for treating the directionality of causation, which Mackie calls "causal priority" and which both he and Mackie agree is a fundamental aspect of causation, as an addition to, rather than as an essential constitutive element of, the sense of "sufficiency" when employed in causal analysis.18 Mackie acknowledged the use of the more discriminating sense of causal sufficiency in common discourse, but he thought it better for the sake of clarity in language use to reserve "sufficiency" for use in its simplest sense: mere lawful sufficiency.19 I have hoped to preserve clarity while not letting language use govern metaphysics by distinguishing between causal sufficiency and mere lawful sufficiency.
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Moore, 2009d, 477. " Moore, 2013b, 334; see Moore, 2009d, 483-5. 18 Moore, 2013b, 335. Moore, 2009d, 482-5. J. L. Mackie, The Cement of the Universe: A Study of Causation (Oxford: Clarendon, 1974), 51-3, 190-2.
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C. Epiphenomena When a condition is a common cause of two different causal "sequences, employing mere lawful sufficiency rather than causal sufficiency can result in erroneously treating conditions in one sequence as causes of the conditions in the other sequence.20 Moore claims that my definition of a causal law does not prevent treating the earlier occurring event on one fork of such an epiphenomenal relation from being treated as a cause of the later occurring event on the other fork: Let c be a common cause of el and e2; let c occur at tl, el at t2, and e2 at t3; let t3 succeed t2 by as small an interval of time as Wright means by "immediate." The occurrence of el' can be sufficient of the occurrence of e2 (the cases are legion - use your imagination); unless "successive" means something causal (Wright's "causal process"?), Wright has no way not to conclude that el causes e2, contrary to what we all know to be true.21 Moore is wrong. He is paying attention only to the words "successional" and "immediate" in my definition of a causal law, while ignoring the rest of the definition. Given the epiphenomenal situation assumed by Moore, there is no empirically derivable abstract set of antecedent conditions containing a condition of type el that, if fully instantiated, would be sufficient for the occurrence of e2 unless a condition of type c also were part of the set, but if that were true then conditions of type el would be unnecessary for the sufficiency of the set. Conversely, if the set did not contain a condition of type c, it would be insufficient regardless of the inclusion of a condition of type el. Of course, this conclusion, like every other causal conclusion, depends upon our having sufficient knowledge of the relevant causal laws or, more likely, their incomplete generalizations. Without such knowledge and pending sufficient experimentation or experience, one might infer a causal relation between el and e2, as with any other set of successive or concurrent events (e.g., the shadow and height of the flagpole). However, for there actually to be a causal relation, causal sufficiency (complete instantiation of the relevant causal laws) must have occurred. D. Pre-emptive causation Moore and others have criticized the NESS account for allegedly being unable to handle properly some types of pre-emptive causation situations. Once again, the criticisms erroneously assume that the NESS account merely requires lawful sufficiency, rather than causal sufficiency. Consider the following often discussed hypothetical: C is a traveler in the desert, whose only source of water is a keg full of water. A adds a fatal dose of undetectable poison to the water in the keg, for which there is no antidote. C remains unaware of the poison in the water. Subsequently, before C drinks any of the poisoned water, B dumps the poisoned water out of the keg. When C attempts to drink water from the keg, she discovers that it is empty. C dies because of dehydration.
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See Wright, "NESS Account," 297.
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Moore, 2013b, 335-6 (citation omitted).
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If we merely require lawful sufficiency and do not qualify the consequence by the time of its occurrence—or perhaps even if we do—we would incorrectly treat the poison as well as the emptying of the keg as duplicative causes of C's death. The poison in the water, along with the other existing conditions, guarantees C's death and thus is lawfully sufficient for its occurrence. On the other hand, if we require necessity—that the condition "made a difference" as a "but for" cause—we would be forced to conclude that neither condition was a cause. In the NESS account, we require causal sufficiency rather than necessity or mere lawful sufficiency—an approach that Moore again incorrectly claims is viciously circular. 22 The causal generalization for death by poisoning includes the victim's drinking the poison, a condition that was not instantiated since the keg was emptied before C was able to drink from it. On the other hand, the causal generalization and the underlying causal laws for death by dehydration, which include as a necessary condition lack of water (and the physical bodily processes that occur as a result of the lack of water), were fully instantiated. Thus, B's emptying of the keg, but not A's poisoning of its contents, caused C's death, even though C may have lived longer as a result of the emptying of the keg. Since Moore refuses to treat negative conditions such as lack of water as causes or effects (but what about the positive condition of the poison in the water?), he denies that either A or B caused C's death, thereby treatingthe death as an uncaused miracle.23 He stands alone in this conclusion, and I have a hard time believing that it fits even his intuitions. Moore until recently argued that attempts to use the NESS account to resolve the causal issue in "late pre-emption" situations are circular and question-begging, because they allegedly simply amount to requiring that the effect was not already caused by something else.24 However, his argument failed to distinguish the necessary conditions in the antecedent of a causal generalization and the distinct condition that constitutes the consequent of the causal generalization.25 For example, although to say that an entity exists or is alive at a certain time obviously entails (in our world) that nothing has caused the entity's destruction or death prior to that time, it should also be obvious that the entity's existence or being alive at a certain time is a state of affairs that is distinct from and not simply the converse of the destruction, death, or non-existence of the entity at a later (remote or immediate) time;26 rather, it is one of the necessary but by itself insufficient conditions for the occurrence of the later event or state of affairs. In his most recent critique of the NESS account, Moore has apparently given up on his claim that the NESS analysis of pre-emption is circular. Instead, he puts forth a new argument: Wright's definition [of a causal law] does not rule out (as being causal) pre-empted feetors in pre-emptive overdetermination cases. In the case of the poison victim about to die from his poisoning who is then shot dead immediately by a second wrongdoer, the 22 25 26
23 24 Moore, 2009d, 495. Moore, 2009d, 144,466-7. Moore, 2009d. 494-5. See Wright, "NESS Account," 300-2. It is unfortunate that on this issue Moore fails to recognize or employ therigorousdistinction between distinct states of affairs that he elsewhere employs (Moore, 2009d, 14-19,281 -2) to distinguish between acts and consequences to rebut arguments that there is no causation requirement in inchoate crimes.
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"poison leads to death" causal law was about to be instantiated in however small an interval of time as Wright means by "immediate." (It's my hypo so I can assure of this with the certainty of an omniscient novelist.) The "instantiation of the consequent" (i.e., here, death) immediately followed the set of conditions (of which poison was here a necessary member) sufficient for death, and that s e t . . . was "fully instantiated." Yet we know that the even more immediately acting bullet killed him, pre-empting the poison.27 If we know (with Moore's omniscience) that the bullet killed the victim, not the poison (or both), then clearly the causal set containing the poison was not fully instantiated; some micro-process had yet to \>e completed, the completion of which required more time than remained before the bullet killed the victim. Or would Moore put the universe on hold? Alternatively, "immediate" means simultaneous with the instantiation of the last condition to be instantiated in the fully instantiated antecedent of the relevant causal law. Either way, the poison was not a cause.
E. Duplicative causation Moore acknowledges that the NESS account properly handles situations involving duplicative causation by two or more independently sufficient conditions, such as two independently sufficient fires or floods that merge and destroy a building, which the sine qua non account mishandles since none of the conditions "made a difference" by being a "but for" cause.28 He also acknowledges the validity and usefulness of the NESS account's ability to identify as causes conditions that were neither strongly necessary nor independently strongly sufficient—for example, each often drops of poison or discharges of pollution when only three such drops or discharges were necessary for the occurrence of the relevant harm 29 —while criticizing the proliferation of causes.30 IV. O m i s s i o n s a n d n e g a t i v e c a u s a t i o n A "positive" condition is the presence of some act, event, or entity in a particular situation; a "negative" condition is the absence of some act, event, or entity in a particular situation. A "positive" or "producing" causal process is one in which all the steps in the process consist of the complete instantiation of one or more causal laws. A "negative" causal process is one in which at least one step in the process involves the failure of a causal law to be completely instantiated, 31 Many philosophers believe that a negative condition cannot be a positive cause, but rather, at best, only a negative cause.32 Some argue that negative conditions cannot be 27 30 31
28 29 Moore, 2013b, 336. Moore, 2009d, 474. See Wright, "NESS Account," 303-5. Moore, 2009d, 487-91. These definitions of positive and negative causal processes differ slightly from my prior definitions, but33the underlying idea is the same. See Wright, "NESS Account," 312. E.g., Ned Hall, "Two Concepts of Causation," in John Collins, Ned Hall, and L. A. Paul (eds.), Causation and Counterfactuals (Cambridge MA: MIT Press, 1994), 225, 253, 260; Jonathan Schaffer, "Causes need not be Physically 'Connected to their Effects: The Case for Negative Causation" ["Negative Causation"], in Christopher Hitchcock (ed.), Contemporary Debates in Philosophy of Science (Oxford: Blackwell, 2004) 197,197-8.
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part of any plausible account of reality and thus cannot be any sort of cause or effect. Moore is most insistent on this point. He notes, correctly, that there are no negative conditions in the sense of the negative opposite of a positive condition, for example non-tramplings by non-elephants. Rather, a negative condition must be understood to be the absence of some positive condition, rather than the "ghostly" reality of its negative opposite. 33 Yet, as Jonathan Schaffer has pointed out, all voluntary human actions and many other actual conditions take place through causal processes in which absences play a critical role: The pattern of negative causation features in even the most paradigmatically causal cases. Suppose that the sniper feels murderous, pulls the trigger, fires a bullet through the victim's heart, and the victim dies, Here is a paradigmatic causal sequence, every step of which is negative causation. Working backwards, surely the firing of the bullet through the victim's heart causes the victim to die. But heart damage only causes death by negative causation: [firing the bullet] (c) causes [a hole (~
