Sextus on Ataraxia Revisited Diego E. Machuca My purpose is to revisit an issue concerning the state of undisturbedness or tranquility (ἀταραξία) in ancient Pyrrhonism as this stance is depicted in Sextus Empiricus's extant works. The issue in question is whether the pursuit and the attainment of undisturbedness in matters of opinion should be regarded as defining features of Pyrrhonism, not merely from a systematic standpoint that examines Pyrrhonism as a kind of philosophy, but mainly according to Sextus's own account of that skeptical stance. In exploring this issue, I will develop an interpretation defended in previous work, responding to some objections, discussing alternative interpretations, offering further textual support, and putting forward new arguments. It is my contention that examining whether the pursuit and the attainment of undisturbedness in matters of opinion are essential to Pyrrhonism makes it possible to gain a more accurate understanding of this brand of skepticism.1 I begin by briefly presenting the standard view among interpreters on the place that undisturbedness occupies in Sextus's Pyrrhonism. I do not spend much time quoting, or referring to, the Sextan texts that are taken to support the standard view because they are familiar ground to specialists and because I wish to focus as much as possible on challenging that view. I then examine four texts that support the claim that neither the search for undisturbedness nor its attainment should be deemed to be defining traits of Pyrrhonism. In so doing, I address some objections that have been, or might be, leveled against my interpretation. I conclude by summarizing the results of my analyses and by briefly describing the features I take to be essential to the Pyrrhonian outlook. I. The Standard View It is safe to say that, when someone with even a slight familiarity with ancient Pyrrhonism thinks about it, two notions come to mind, namely, suspension of judgment (ἐποχή) and undisturbedness. The fact that the latter notion springs to mind is perfectly reasonable. To begin with, undisturbedness is mentioned in the definition of skepticism that Sextus offers at the beginning of the Pyrrhonian Outlines (PH): The skeptical [way] is an ability to set up oppositions (δύναμις 1 Henceforth, whenever I talk about undisturbedness tout court, I refer to undisturbedness in matters of opinion; and whenever I ask whether undisturbedness is essential to Pyrrhonism, I mean both the pursuit and the attainment of undisturbedness. Also, following Sextus, I employ 'Pyrrhonist' and 'skeptic' interchangeably. Ancient Philosophy 40 (2020) ©Mathesis Publications 435 ἀντιθετική) among things that appear and things that are thought in any way whatsoever, an ability from which we come, through the equipollence (ἰσοσθένεια) in the opposed objects and arguments, first to suspension of judgment and after that to undisturbedness.2 (PH i 8) In addition, the search for undisturbedness explains why the prospective skeptic devoted himself to philosophy (PH i 12, 26, 29); undisturbedness is part of the full-blown skeptic's twofold aim (PH i 25, 30, 215; cf. i 10); it is the state of mind that has closely and unexpectedly followed or accompanied suspension (PH i 8, 10, 26, 29, 31, 205, 232); and it is that for the sake of which the skeptic deals with physical, logical, and ethical matters (PH i 18). Sextus also tells us that, contrary to the belief that things are by nature good or bad, the adoption of suspension on the matter makes it possible to attain undisturbedness and happiness, and hence to live acceptably (PH i 28, Adversus Dogmaticos [AD] v [= AM xi] 111, 144, 160, 168; see also PH iii 235, AD v 147, 150). It is therefore no surprise that the great majority of interpreters regard undisturbedness as a defining feature of Sextan Pyrrhonism. This view is not usually expressed in an explicit way, for the simple reason that, except in special circumstances, it does not make much sense to state the obvious. But we do find Barnes 1990, 2691 remarking that the 'point of Pyrrhonism is ἀταραξία', Moller 2004, 437 claiming that the Pyrrhonist's aim of undisturbedness 'appears to be essential, for without it his way of life seems imperiled', and Perin 2010, 9 maintaining that 'the ability to achieve tranquility through suspension of judgement is constitutive of Scepticism' and that 'the pursuit of tranquility by way of suspension of judgment is an essential feature of Scepticism' (2019, 135n16). In a similar vein, McPherran 1989, 166 has argued that the desire for undisturbedness is a 'natural desire'-understanding 'natural' as 'what is necessitated within us'-and that, given that 'it appears to be impossible to purge human nature of its necessary desires, it would be pointless for the Skeptic to try to subject the natural desire for ἀταραξία to Skeptical suspension of judgment' (1989, 165). To the extent that the quest for undisturbedness is to be explained as the product of a necessary desire shared by all humans, it seems that the Pyrrhonist's pursuit of that state is to be interpreted as an essential (albeit not distinctive) feature of his outlook. From a contemporary vantage point, Sextus's references to undisturbedness (and also to happiness) sound foreign to most of us. The claim that it is the aim of skepticism sounds strange because professional or academic philosophy does not have much to do with our peace of mind (or our happiness or well-being) anymore. And the claim that undisturbedness follows upon suspension sounds strange because the idea that one can get rid of a considerable amount of the dis2 When referring to skepticism, Sextus often employs the phrase ἡ σκεπτικὴ ἀγωγή or simply ἡ σκεπτική, by which he means the skeptical way, way of thought, way of life, or orientation. The translations of Sextus's texts are my own, but I have consulted Bury trans. 1933, 1949; Mates trans. 1996; Pellegrin trans. 1997; Blank trans. 1998; Annas & Barnes trans. 2000; Pellegrin et al. trans. 2002; and Bett trans. 2018. 436 turbance one experiences in life by suspending judgment about everything3 strikes at least most of us as unrealistic.4 Both facts are no doubt among the reasons why discussions of Pyrrhonian skepticism in contemporary analytic philosophy have either entirely ignored Sextus's reference to undisturbedness, or briefly mentioned it only to immediately set it aside as a curious and irrelevant element in his account of Pyrrhonism. Such discussions have focused almost exclusively on the epistemological implications of the so-called Five Modes of Agrippa. Pyrrhonism has survived primarily either as a form of epistemological skepticism or as a form of skepticism about epistemology.5 To my mind, another reason for the lack of interest in Sextus's remarks on undisturbedness among contemporary analytic philosophers is that, from a systematic vantage point, nothing essential is lost in the Pyrrhonian outlook if both the search for undisturbedness and its attainment are set aside. In the next section, I attempt to show that such a systematic view on Pyrrhonism is in accord with Sextus's own stance inasmuch as in his writings one finds textual evidence that he himself did not regard undisturbedness as a defining feature of his skepticism. II. Challenging the Standard View In Machuca 2006, 124-129, I proposed an interpretation that runs counter to the picture of Pyrrhonism predominant among specialists in that it claims that undisturbedness should not be viewed as essential to the Pyrrhonian outlook. More precisely, I argued, on the basis of three passages (PH i 25, 232; Adversus Mathematicos [AM] i 6), that neither the pursuit nor the attainment of undisturbedness in matters of opinion are defining features of Pyrrhonism. I distinguish between the pursuit of such a state of mind and its attainment because it 3 A reviewer has observed that, while the phrase 'a considerable amount of the disturbance one experiences' suggests that, before suspending judgment, the skeptic was disturbed over particular cases (he was disturbed over whether p or not-p, whether q or not-q, etc.), his disturbance was more general and did not concern particular cases. I should first note that my reason for using that phrase is simply that Sextus remarks that the skeptic is not free from all disturbance and hence cannot attain complete happiness: he is disturbed by certain things that impose themselves upon him, such as thirst and hunger (PH i 29; AD v 143, 148-150, 156-158; cf. PH i 13, 24). Second, I find no reason for claiming that the prospective skeptic was not disturbed over particular cases. Take the case of evaluative matters: it may be argued that what produces distress is the belief that a specific x is objectively good or bad, for it seems that only that kind of belief has an object that one can either (i) intensely pursue, be excited to have gotten hold of, and be afraid of losing, if one believes it to be good, or (ii) intensely avoid and be tormented to have gotten hold of, if one believes it to be bad (cf. Machuca 2019b, 199n14). 4 This is not to say that one can simply discard Sextus's report on his own experience as false. I think that whether it is possible for someone to attain (some degree of) undisturbedness by suspending judgment ultimately depends on his temperament and personal history (cf. McPherran 1989, 150; Machuca 2006, 124 and 2019c, 49-50). 5 I make this distinction because Pyrrhonism has been conceived of in both ways: whereas some believe that the Pyrrhonist is committed to the criteria of epistemic justification underlying the Agrippan modes, others think that he makes a merely dialectical use of them and has no epistemological commitments whatsoever. For some discussion of these issues, see Machuca 2015. 437 might be the case that, even if the Pyrrhonist does not succeed in attaining it, he continues to be a Pyrrhonist insofar as he keeps on searching for it. Alternatively, it might be the case that, even if the Pyrrhonist stops searching for undisturbedness, he continues to be a Pyrrhonist insofar as he attains that state of mind after suspending judgment. In what follows, I revisit the three passages in question, offer new considerations in favor of my interpretation of them, answer some objections, consider and reject alternative interpretations, and examine a fourth passage (PH i 12) that further supports my interpretation. But before doing so, let me go back to PH i 8, a passage cited at the beginning of the previous section. The definition of skepticism provided at PH i 8 may in principle be read in two different ways (Nussbaum 1994, 286). According to the first reading, skepticism is defined exclusively as the ability to set up oppositions among things that appear and that are thought in any way whatsoever, and it is then added that equipollence, suspension, and undisturbedness just happen to be three results that have so far followed from the exercise of that ability. According to the second reading, skepticism is defined also by those three results, so that it is the ability that, by opposing perceptual and intellectual appearances to each other, produces such results. The second reading is to be preferred for two reasons. First, it is implausible that Sextus would define skepticism merely as an oppositional ability, since this does not distinguish it from other philosophies that made use of that ability, such as Protagoreanism and so-called Academic skepticism. The second reason is that it is supported by PH i 25, where, when explaining the skeptical aim, Sextus tells us that 'an aim is that for the sake of which all things are done or considered, but that [is not done or considered] for the sake of anything else; or [an aim is] the final object of desires'. Given that these are standard definitions accepted by Epicureans, Stoics, and Peripatetics (Annas and Barnes 2000, 10nn47-48), one might think that Sextus does not endorse them, but makes use of them because doing so makes it possible to engage with his dogmatic rivals and/or because such conceptions of the aim still exert a merely psychological influence on him. Be that as it may, if undisturbedness is the skeptic's goal, then it can be argued that his exercise of the δύναμις ἀντιθετική is aimed at that state of mind and that his attainment of it after suspending judgment is to be considered as part of the definition of skepticism. In that case, both the search for undisturbedness and its attainment would have to be deemed essential to Pyrrhonism. Note, however, that the fact that all of a person's actions are aimed at achieving a given goal does not imply that the choice of this goal is inexorable or that it cannot be abandoned and replaced by a different one. In addition, there are reasons for claiming that, if at some point the skeptic's δύναμις ἀντιθετική continued to lead to equipollence and suspension, but not to undisturbedness, he would not regard this as the loss of a defining feature of his stance. As already noted, the interpretation according to which neither the pursuit nor the attainment of undisturbedness are essential to Pyrrhonism is supported by four passages of Sextus's extant works: PH i 12, 25, 232, and AM i 6. I analyze them in this order: PH i 25, PH i 12, AM i 6, PH i 232. 438 It is useful to quote the relevant segment of PH i 25 together with the whole of the following section: [25] We say up to now (φαμὲν δὲ ἄχρι νῦν) that the skeptic's aim is undisturbedness in matters of opinion and moderation of affection in things unavoidable. [26] For having begun to philosophize with the aim of deciding among the appearances (τὰς φαντασίας) and apprehending which are true and which false, so as to become undisturbed, he encountered an equipollent disagreement (ἰσοσθενῆ διαφωνίαν); being unable to decide it, he suspended judgment. And while he was suspending judgment, undisturbedness in matters of opinion closely followed him by chance. How is the temporal qualifier ἄχρι νῦν, which governs φαμέν, to be understood? As far as I can see, in a straightforward way. The skeptic says up to now that part of his aim is undisturbedness because this state of mind has thus far appeared to him to be so, and he leaves open the possibility that he might say otherwise in the future because things might appear differently to him in the future. Hence, up until now the skeptic has desired to attain the state of undisturbedness, and so has searched for it, but he cannot rule out the possibility that, in the future, he might pursue a different aim on account of the influence of any number of circumstantial factors. Sextus is therefore recognizing that undisturbedness might cease to appear to the skeptic as a state of mind worth experiencing. He is also recognizing that the skeptic, qua skeptic, might pursue a different aim: the aim of skepticism may change, but once the change is completed, one will still be talking about the aim of skepticism. The story told at PH i 26 explains the remark made at PH i 25 because it describes what happened to be the skeptic's philosophical itinerary from dogmatism to skepticism.6 The skeptic embarked on philosophy because he wished to become undisturbed, but he could have done so for a different reason and he might remain engaged in philosophy for a different reason. In fact, as Perin 2010, 24 has pointed out, the skeptic has an interest in the discovery of truth for its own sake, since otherwise he would lack a motive for seeking undisturbedness. For Sextus tells us at PH i 12 and 26 that the skeptic seeks undisturbedness because he is distressed by the unresolved conflict of appearances, and hence by his not knowing whether p or not-p is the case. This means that the skeptic has an interest in knowing, and hence a desire to know, whether p or not-p is the case. The fact that such a desire is unsatisfied is a source of distress for him and it is this distress that motivates his desire for undisturbedness.7 Thus, the skeptic's interest in knowing the truth cannot be an interest in this knowledge as a means to undisturbedness, i.e., cannot presuppose the desire for undisturbed6 This story could be read either as a real historical account of what occurred to some skeptics or as a merely speculative account by Sextus or one of his skeptical sources. 7 As I have argued elsewhere (Machuca 2011, 253; 2013, 209; 2019b, sect. 4), the ultimate reason why unresolved conflicts were a source of disturbance for the prospective skeptic is not an unsatisfied desire, but the belief that discovering the truth is of objective value. 439 ness, since that interest is ultimately the source of this desire. Hence, even if the prospective skeptic lacked any interest in becoming undisturbed, his inquisitive temperament could well explain his initial engagement in philosophic inquiry; and even if the full-blown skeptic lacked any such interest, his inquisitive temperament could well explain his ongoing engagement in philosophic inquiry.8 If my interpretation of PH i 25 is on the right track, then giving up the search for undisturbedness would not prevent the skeptic from remaining a skeptic. As we saw in section 1, Moller 2004, 436-437 and 440 regards undisturbedness as being essential to the skeptic's way of life. He offers two reasons for his view. First, the Pyrrhonist's possession of the aim of undisturbedness explains his interaction with dogmatists: his philanthropy results in interacting with dogmatists because it appears to him that doing so will cause them to achieve that aim (cf. PH iii 280-281). Second, the Pyrrhonist's possession of that aim explains his exercise of the ability to set up oppositions among arguments that strike him as equipollent: his application of this ability makes it possible to preserve the state of being undisturbed (PH i 8). It should first of all be noted that Moller's view of undisturbedness as being an essential feature of Pyrrhonism is prima facie surprising inasmuch as he recognizes that PH i 25 refers to the 'apparently provisional nature of the Skeptic's aim' and 'seems to allow that at any moment the Skeptic may adopt some other aim' (2004, 437).9 However, he thinks that PH i 25 poses the significant problem that, without the aim of undisturbedness, it is not possible to account for the two crucial aspects referred to above. Actually, the problem is only an apparent one, because the interaction with dogmatists and the exercise of the δύναμις ἀντιθετική can be accounted for without reference to undisturbedness and in a way that is perfectly in line with the Pyrrhonian outlook. They could, for instance, be accounted for by reference to the Pyrrhonist's inquisitive temperament, which together with his suspensive attitude triggers his 8 A reviewer has leveled the following objection. Though it is true that the inquisitive temperament Sextus attributes to the skeptic could explain why the skeptic engages in philosophical inquiry, engaging in philosophical inquiry is one thing, doing so as a skeptic another. The inquisitive temperament is at best necessary, but not sufficient, for doing philosophy in the way that makes one a skeptic. On a plausible reading of PH i 12 (a text to be analyzed below), Sextus himself recognizes that this inquisitive temperament is not unique to the skeptic. On that reading, Sextus says only that skeptics are a subset of those who are μεγαλοφυεῖς (men of talent): every person who becomes a skeptic is μεγαλοφυής, but not every person who is μεγαλοφυής becomes a skeptic. Hence, the skeptic's inquisitive temperament, and the desire to know the truth it gives him, is not by itself enough to explain why the skeptic would remain a skeptic even if he were to give up the goal of undisturbedness. In reply to this objection, it should be pointed out that the inquisitive skeptic would remain a skeptic, even if undisturbedness ceased to be his goal, provided that the conflicting views examined in his ongoing inquiries struck him as equipollent, and hence provided that the result of his inquiries was suspension. It is the inability to settle the disagreements that confront him, together with his inquisitive temperament, that makes him keep engaged in philosophical inquiry in a skeptical manner, that is, without doxastic commitments and with a critical and open-minded attitude. When he first engaged in philosophical inquiry, his approach was no different from that of any other inquirer or any other μεγαλοφυής. But once all of the inquiries he carried out ended up in suspension, his approach in his ongoing inquiries became that of a skeptic. 9 I should note that, at the time I wrote Machuca 2006, I had not read Moller 2004. 440 ongoing inquiry into truth (PH i 1-3, ii 10). The Pyrrhonist's open-minded and argument-driven inquiry can be undertaken either through personal reflection or by engaging in debate with the dogmatists (see AD i [= AM vii] 1 and Machuca 2019a, 211-212). Hence, he could well engage in an argumentative exchange with dogmatists, not in order to persuade them and induce them to suspend judgment because it appears to him that they might thus attain the state of undisturbedness, but as a way of carrying out his philosophical investigations. The same goes for the Pyrrhonist's exercise of the δύναμις ἀντιθετική, which can be applied either in debate with the dogmatists or in the examination, through personal reflection, of the epistemic credentials of the arguments that have been put forward by others or that he himself has come up with. Perin 2019 maintains that my argument to the effect that the temporal qualifier ἄχρι νῦν shows that the Pyrrhonist could abandon undisturbedness as his ultimate goal without ceasing to be a Pyrrhonist is more powerful than I recognize and, moreover, stronger that I want it to be. The reason is that such a temporal qualifier has wider scope than I acknowledge inasmuch as, at PH i 4, Sextus remarks that everything he says about skepticism is governed by it. From this, it would follow that any feature Sextus attributes to Scepticism is a feature it appears to Sextus or the Sceptic to have at the moment (νῦν) or up to now. Hence, it will follow from Machuca's argument [in Machuca 2006] that none of the features Sextus attributes to Scepticism are, according to Sextus, essential to it. But Machuca himself wants to count some features but not others (including the pursuit of tranquility) as essential features of Scepticism. We can preserve the view that some features Sextus attributes to Scepticism are understood by him to be essential to it by giving the temporal qualifier wide scope. On this reading, Sextus does make claims of the form 'X is an essential feature of Scepticism' but those claims fall within the scope of the temporal qualifier. Sextus says, in effect, that up to now or as things are now, it is the case (or it appears to me) that X is an essential feature of Scepticism. On this reading, pace Machuca, the pursuit of tranquility is taken by Sextus to be an essential feature of Scepticism. It is just that Sextus does not want to rule out the possibility that his conception of Scepticism and what's essential to it will change. (Perin 2019, 135n16) Thus, in Perin's view, the temporal qualifier used at PH i 25 does not indicate that Sextus is talking about non-defining features of skepticism; rather, it qualifies Sextus's remarks about some of the defining features of skepticism. It is true that, according to PH i 4, everything Sextus says in PH must be understood as a description of what appears to him at the moment (κατὰ τὸ νῦν φαινόμενον). However, although he often uses νῦν and ἄχρι νῦν to restrict the temporal scope 441 of his remarks, they are just not the same temporal qualifier. The preposition ἄχρι cannot be regarded as irrelevant or redundant unless a reason is provided for claiming that its use does not add anything to the meaning of the adverb νῦν. The natural or default reading of PH i 25 is not that according to which the meaning and function of ἄρχι νῦν are no different from the meaning and function of νῦν at PH i 4. Rather, the natural or default reading is that, in using ἄρχι νῦν, Sextus wants to emphasize that what he writes applies up to now and that he cannot rule out the possibility that things might change in the future: up to this point, skeptics say that undisturbedness is their goal because up to this point it is something they have desired to attain, but they leave open the possibility that they, qua skeptics, might pursue a different goal in the future.10 In order to further support my reading of ἄρχι νῦν and my view that undisturbedness is not one of the defining features of Pyrrhonism, imagine Sextus saying any of the following: 'We say up to now that the Pyrrhonist suspends judgment about everything, but he might start holding some beliefs in the future'; 'We say up to now that the Pyrrhonist lives by following his appearances, but at some point he might start making decisions on the basis of beliefs'; 'We say up to now that the Pyrrhonist sets up oppositions among perceptual and intellectual appearances, but in the future he might doxastically assent to certain appearances without examining the epistemic credentials of conflicting appearances'; 'We say up to now that the Pyrrhonist is engaged in ongoing investigation of the truth, but in the future he might abandon his inquiries because he might come to the conclusion that the search for truth is forever doomed to failure'. Each of these utterances strikes us as utterly odd. Of course, they are not odd if what they are saying is that, at some point in the future, the Pyrrhonist might cease to be a Pyrrhonist. But they are without a doubt odd if what they are saying is that a Pyrrhonist, qua Pyrrhonist, might do any of those things (to hold beliefs, to act on the basis of beliefs, etc.) at some point in the future. By contrast, the utterance 'Up to now we say that the Pyrrhonist's aim is undisturbedness in matters of opinion, but he might have a different aim in the future' does not strike us as equally odd, the reason being that the Pyrrhonist, qua Pyrrhonist, may have a different goal or a different initial motivation for engaging in philosophy. As a matter of fact, Sextus does not use the temporal qualifier ἄχρι νῦν to talk about any of the above four features of Pyrrhonism (suspension of judgment, living by appearances, producing oppositions, engagement in ongoing inquiry) in the way he uses it to talk about undisturbedness at PH i 25. I do not think this is an accident. But if it is, then we need a reason for so claiming. The second passage I take to support the interpretation that undisturbedness is 10 That my reading of ἄχρι νῦν is not unnatural gets some support from the fact that others interpret it in a similar way. As we saw above, Moller 2004, 437 claims that PH i 25 refers to the 'apparently provisional nature of the Skeptic's aim' and 'seems to allow that at any moment the Skeptic may adopt some other aim'. Bett 2015, 41n28 remarks that, at PH i 25, ἄχρι νῦν is used to make it clear that the 'end is put forward as a report of the sceptics' own experience...not as what human beings in general should or naturally do pursue...or even as what the sceptics are committed to pursuing in the future'. 442 not essential to Pyrrhonism is PH i 12, where Sextus distinguishes between the causal principle and the chief constitutive principle of skepticism: The causal principle of the skeptical [way] is the hope of becoming undisturbed. For men of talent, disturbed by the variation in things (τὴν ἐν τοῖς πράγμασιν ἀνωμαλίαν) and being in aporia as to which of them they should rather assent to, came to investigate what is true in things and what is false, so as to become undisturbed as a result of this distinction. But the main constitutive principle of the skeptical [way] is that to every argument an equal argument is opposed. For we think that from this we come to hold no beliefs (εἰς τὸ μὴ δογματίζειν). By the 'causal principle' (ἀρχὴ αἰτιώδη) of skepticism Sextus refers to that which triggered the skeptic's initial engagement in philosophy, i.e., his original motivation for embarking on philosophical investigation. Generally speaking, this kind of motivation is merely circumstantial: what triggers one person's interest in philosophy may be completely different from what triggers another's; what motivates a person to keep engaged in philosophical inquiry may be distinct from what motivated him when he first embarked on philosophy; and a person may have first engaged in philosophical inquiry motivated by a given aim, then abandoned the inquiry, and resumed it later on motivated by a different aim. In my view, what Sextus is saying at PH i 12 and i 25 is that a prospective skeptic could have embarked on philosophy motivated by an aim different from undisturbedness; or that a full-blown skeptic may have a different motivation for keeping engaged in philosophical inquiry; or that a skeptic who has abandoned philosophical inquiry might undertake it again motivated by an aim that is no longer the state of undisturbedness he was seeking the first time he embarked on that inquiry. We should keep in mind that the fact that undisturbedness happened to motivate or trigger the Sextan skeptic's initial engagement in philosophy is to be explained by his cultural and philosophical context. For instance, two of his main dogmatic rivals, namely, the Stoics and the Epicureans, considered undisturbedness to be the principal component of happiness (McPherran 1989, 138; Striker 1996, 185-188; Bett 1997, 144). Moreover, the two definitions of the aim given at PH i 25 are, as already noted, standard definitions accepted by both Stoics and Epicureans. I believe that Sextus would accept that factors of this kind exert an influence on both the prospective skeptic and the full-blown skeptic-just as he accepts that the latter is influenced by the laws and customs of the community to which he happens to belong (PH i 23-24)-and that in a different context they would be exposed to the influence of factors that would awaken no interest in undisturbedness.11 Note in this regard that, at DL ix 107, Diogenes Laertius 11 Moller 2004, 434-435, 439-440 argues that the trouble with the Pyrrhonist's taking undisturbedness as his final aim is that neither the adoption of a final aim nor the choice of undisturbedness can be regarded as 'the products of the involuntary workings of our minds and bodies...nor are they part of the fabric of our everyday, non-theoretical life that we absorb through custom and nature'. 443 points out that, according to Timon and Aenesidemus, the skeptic's aim 'is suspension of judgment, which undisturbedness follows as a shadow'. It thus seems that some people who are skeptics may not adopt undisturbedness as their aim. As we will see when examining PH i 232, Sextus seems to acknowledge this. It should also be noted that, at PH i 30, he remarks that 'some among the eminent skeptics have added to them [i.e., ἀταραξία and μετριοπάθεια] also suspension of judgment in the investigations'. Although the skeptics in question take undisturbedness as an aim, this passage is important because Sextus recognizes that skeptics may have other aims. To refer to the other principle of skepticism, Sextus uses the phrase συστάσεως τῆς σκεπτικῆς ἀρχὴ μάλιστα, which literally means 'the main principle of the constitution of the skeptical [way]'. While the hope of becoming undisturbed is the originating cause of skepticism, the activity of opposing to every argument a rival argument that strikes the skeptic as equally credible is its main, chief, or foremost principle. The term σύστασις means the composition, the structure, or the constitution of someone or something. Hence, Sextus is talking about that which constitutes the very structure of skepticism and, one may therefore argue, that which defines whether someone is a skeptic.12 It is also worth emphasizing that Sextus introduces the main constitutive principle of skepticism by using δέ, by which, to my mind, he seeks to contrast it with the circumstantial aim whose search triggered the skeptic's initial engagement in philosophical inquiry and eventually landed him on suspension. It makes perfect sense to say that the activity of opposing to each other arguments that turn out to be equipollent is the constitutive principle of skepticism. For, at PH i 8, this philosophy is first of all Hence, even if described as a residual habit or disposition, the Pyrrhonist's adoption of undisturbedness as the ultimate goal is heavily theoretical. In response, it should first be noted that the persistent influence of theoretical views that the Pyrrhonist used to endorse can be explained by the fact that he is naturally capable of both perceiving and thinking-which is one of the four parts of his criterion of action (PH i 23-24)-and that there is no reason for regarding the capacity to think in question as rudimentary, crude, or unsophisticated. Secondly, in order to understand the Pyrrhonian stance, the emphasis should be placed not so much on the origin of one's habits or dispositions-i.e., on whether they are grounded in theory or in everyday life-as on the attitude taken towards those habits or dispositions. For the real issue is whether one is doxastically committed to one's theoretical or practical habits or dispositions, that is, whether one takes them to be true, correct, or justified. The Pyrrhonist's stance is defined by the lack of any such doxastic commitment. 12 A reviewer has objected that the constitutive principle of skepticism does not refer to that which defines whether someone is a Pyrrhonist, but rather to the Pyrrhonist's method or to the principle of organization of his inquiry. In reply, note first that, as I point out in the next paragraph in the body of the text, insofar as that principle refers to the activity of producing oppositions among arguments that appear to the Pyrrhonist to be equipollent, it refers to his suspension of judgment about which of the conflicting arguments is sound. Second, as the reviewer seems to recognize, the constitutive principle explains the way in which the Pyrrhonist carries out his open-minded and truthdirected inquiry. Thus, that principle refers to two of the defining features of skepticism (see section 3 below). Finally, Sextus remarks that the activity of producing oppositions among equal arguments is the constitutive principle of skepticism because, in virtue of his engagement in it or in virtue of having the ability to engage in it, the Pyrrhonist does not hold beliefs, thereby differing from his dogmatic rivals. 444 defined as the ability to set up oppositions that results in certain mental states due to the fact that the opposing arguments strike the exerciser of that ability as equally credible or persuasive. In sum, I take it that, while there might be a different causal principle or origin of skepticism, that is, a different motivation for embarking on philosophical investigation that has so far resulted in suspension, there might not be a different constitutive principle for the simple reason that, if there were one, then skepticism would cease to be what it is. It is worth noting that, in Sextus's characterization of the constitutive principle of skepticism, there is a reference to the skeptic's suspension and inquiry. Regarding suspension, not only are the opposed arguments described as equal- and we know that equipollence results in suspension (PH i 8, 196)-but we are also told that the main constitutive principle of skepticism leads the skeptic to refrain from 'dogmatizing', that is, from holding beliefs or opinions, and this is precisely what suspension consists in. As for the activity of inquiry, note that the skeptic's inquiry consists mainly in opposing arguments to each other in order to assess their epistemic credentials. Moreover, any reference to the skeptic's suspension implies a reference to his inquiry inasmuch as his suspension does not consist in his refraining from holding opinions about issues he has not considered, but rather results from the careful scrutiny of issues regarding which he has so far found no answers. Sextus explicitly describes suspension as a mental state or condition in which the Pyrrhonist finds himself after having undertaken an investigation (PH i 7) and that results from the equipollence of the matters being investigated (PH i 196). The importance of these remarks concerning suspension and inquiry lies in the fact that it could be objected that, on my reading of PH i 12, it is a sufficient condition, and not merely a necessary condition, for being a skeptic that a person be a man of talent who is distressed by his inability to determine the truth about certain matters, and who is therefore motivated to determine the truth about those matters in order to alleviate this distress (cf. n8 above).13 But this in no way follows from my reading of the passage, which explicitly describes the skeptic as someone who carries out his philosophical investigations by producing oppositions among arguments that appear to him to be equally credible or persuasive, and who ends up suspending judgment after each one of those investigations. A crucial difference between the skeptic and the man of talent he used to be is that he no longer engages in philosophical inquiry with the conviction both that there is a truth to be found regarding the matters under investigation and that he is able to find it-without this meaning, of course, that he believes that there is no such truth or that he is unable to discover it. On my reading of PH i 12, then, this passage supports the view that the search for undisturbedness is not essential to Pyrrhonism, for a prospective skeptic may have a different motivation for engaging in inquiry. It might be argued that PH i 12 does not support the same conclusion regarding the attainment of undisturbedness, for this state of mind is, according to PH i 8, a result of setting up oppositions among arguments that strike one as equipollent, which is the main 13 This objection was raised by an anonymous reviewer. 445 constitutive principle of skepticism. In my view, if there is a reference to the attainment of undisturbedness, it is at most implicit, unlike those to suspension and inquiry. But I grant that PH i 12 can be taken to support only the view that the pursuit of undisturbedness is not a defining feature of Pyrrhonism. Before turning to the examination of AM i 6, I would like to consider one of the passages referred to in the previous section that seem to support the standard view on the central place that undisturbedness occupies in Sextus's Pyrrhonism: For we do not inquire into natural phenomena (οὐ φυσιολογοῦμεν) in order to make assertions with confidence about any of the matters dogmatically treated in relation to the inquiry into natural phenomena (τῶν κατὰ τὴν φυσιολογίαν δογματιζομένων). But we do touch on this inquiry in order to be able to oppose to every argument an equal argument and for the sake of undisturbedness. In this way, too, we approach the logical and ethical parts of so-called philosophy. (PH i 18) It may be argued that the remark that the skeptic engages in the study of natural, logical, or ethical matters also for the sake of undisturbedness runs counter to my interpretation. However, I think that, although he is not explicit about this, Sextus can be taken to be describing what the skeptic has done up to this point and referring to a motivation the skeptic has so far had. Someone might claim that the καί in the second sentence of the quoted passage is epexegetical: 'in order to be able to oppose to every argument an equal argument, that is, for the sake of undisturbedness'. The skeptic opposes equal arguments to each other only because this enables him to attain undisturbedness. This interpretation cannot be correct, though: given that in that sentence Sextus is referring to the causal and the constitutive principle of skepticism explained at PH i 12, if the καί were epexegetical, then at PH i 18 he would be conflating the two principles. Hence, there are two independent reasons for the skeptic's engagement in the inquiry into natural phenomena (cf. Machuca 2019b, sect. 3). The first, which refers to the main constitutive principle of skepticism, is to be explained by reference to the skeptic's inquisitive temperament, which motivates him to assess the epistemic credentials of the claims, arguments, and doctrines advanced by the dogmatists.14 The second, which refers to the causal principle of skepticism, is to be explained by a desire that the skeptic happened to have and that he might stop having while remaining a skeptic. Let us focus now on AM i 6, where we read: [The skeptics] experienced the same sort of thing with regard to the disciplines (μαθημάτων) as they did with regard to the whole of philosophy. For just as they approached the latter with the desire of reaching the truth, but suspended judgment 14 Perin 2010, 118n6; 2018, 127n12 fails to see that PH i 18 is not incompatible with the skeptic's ongoing engagement in philosophical investigation because he does not realize that producing oppositions among claims or arguments so as to assess their epistemic credentials is the skeptic's main way of carrying out his inquiries. 446 when confronted with the equipollent conflict and the variation of things (ἰσοσθενεῖ δὲ μάχῃ καὶ ἀνωμαλίᾳ τῶν πραγμάτων), so too with regard to the disciplines they set out to acquire them, seeking to learn the truth here as well, but when they discovered equal aporias, they did not conceal them. When I first read this passage many years ago, I was surprised by the fact that there is no reference to the skeptic's pursuit and attainment of undisturbedness. Unlike what we find at PH i 12, 26, and 29, undisturbedness is neither said to be the reason why the skeptic embarked on philosophy-i.e., its causal principle- nor mentioned as the state of mind that up to this point has closely followed suspension of judgment. By contrast, all the other elements of the story of the Pyrrhonist's philosophical journey are present: the search for truth, the variation in things, the conflict among equipollent positions, the discovery of aporias, and the adoption of suspension of judgment. It seems to me that, if either the pursuit or the attainment of undisturbedness were central features of Pyrrhonism, Sextus would have mentioned them in the quoted passage. What reason could he have had for such an omission if not the fact that it appeared to him that they were not essential to his skeptical stance? It might be argued that Sextus left out any reference to the pursuit and attainment of undisturbedness both because the only reason he devoted himself to the μαθήματα was his interest in discovering the truth, and because undisturbedness did not follow suspension of judgment regarding the μαθήματα. In order to accept this line of argument, one would have to explain, first, why holding beliefs about the μαθήματα does not cause disturbance. More precisely, one would have to explain why the prospective skeptic did not believe that discovering the truth about the μαθήματα is of objective value-thereby avoiding the distress that results from holding that belief- whereas he did hold an evaluative belief concerning the discovery of the truth about all other matters (cf. n7 above). And second, one would have to explain why undisturbedness did not follow suspension of judgment regarding the μαθήματα, whereas it did follow suspension of judgment regarding all other matters. It might also be argued that, at AM i 6, Sextus says nothing about the pursuit or the attainment of undisturbedness because it is clearly implied and so need not be mentioned explicitly: it is clearly implied because, given what Sextus says elsewhere, the skeptic pursues the discovery of truth in order to achieve undisturbedness, and he achieves this state of mind by suspending judgment.15 The problem with this line of argument is that one could pose the following question: why did Sextus feel the need to explicitly mention all the other elements of the story of the Pyrrhonist's philosophical journey? If he took for granted that the readers of AM were already familiar with his other works, why did he not limit himself to remarking that the skeptic's experience with regard to the disciplines was the same as his experience with regard to the whole of philosophy? The line of argument in question does not explain why there is only one omission at AM i 6, whereas my interpretation of the passage does offer such an explanation. 15 This line of argument was suggested by an anonymous reviewer. 447 It might finally be argued that perhaps the way the issue struck Sextus at the time he wrote AM was different from the way it struck him at the time he wrote PH-no matter what their chronological order is-and that whereas in AM he does not take undisturbedness to be essential to his stance, in PH he does. However, as I tried to show in my analysis of PH i 12 and i 25, and as I will try to show in my analysis of PH i 232, we find in PH strong evidence to the effect that Sextus did not regard undisturbedness as a defining feature of Pyrrhonism. It could be objected that, in my analysis of AM i 6, I am putting forward an argumentum ex silentio: from the fact that in that passage nothing is said about either the search for undisturbedness or its attainment, it follows that Sextus is suggesting or implying that neither is a defining feature of skepticism. The problem with this argument is that, the objection goes, arguments from silence are fallacious. In my view, however, the soundness of an argument from silence applied to the interpretation of a passage should be assessed taking into consideration the context in which the omission occurs. More generally, we should bear in mind that the slogan 'Absence of evidence is not evidence of absence' is not true in all cases. In forensics, absence of evidence is sometimes evidence of absence: the absence of gunshot residue on the hand of a person whose death was caused by a firearm indicates that he did not commit suicide if, among other things, tests reveal that the gun leaves such residue when fired. In general, absence of evidence is evidence of absence in case one has reason to believe that, if p were true, then one would have positive evidence that it is true. In the case of AM i 6, it seems to me that, if either the pursuit or the attainment of undisturbedness played as fundamental a role in Pyrrhonism as most interpreters believe, then Sextus would have made explicit or implicit reference to them in the description of the Pyrrhonist's philosophical itinerary from dogmatism to skepticism offered in that passage. I take AM i 6 to be the kind of context in which an argument from silence is not fallacious because, given that all the other elements of the Pyrrhonist's philosophical itinerary are briefly and explicitly mentioned in the passage, one would have expected the same kind of brief and explicit mention of the pursuit and attainment of undisturbedness. In any case, the significance of AM i 6 cannot be fully appreciated when examined in isolation, but only in connection with PH i 12, i 25, and the text to be analyzed next. The fourth text that can be taken to support my interpretation is the passage of the first book of PH in which Sextus considers whether Arcesilaus's outlook is the same as the Pyrrhonist's. He points out that Arcesilaus certainly seems to me to share the Pyrrhonian discourse (τοῖς Πυρρωνείοις λόγοις), so that his orientation (ἀγωγήν) and ours are almost one and the same. For he is not found making assertions about the reality or unreality of anything, nor does he prefer any one thing to another in respect of credibility and lack of credibility, but suspends judgment about everything. And [he says] that the aim is suspension of judgment, which we said is accompanied by undisturbedness. He also says that 448 partial suspensions of judgment are good and partial assents bad. (PH i 232-233) In the final segment of the Pyrrhonian Outlines (PH i 209-241) devoted to exploring the differences between Pyrrhonism and its neighboring or nearby philosophies, Sextus's main reason for refusing to consider a given philosophy as skeptical is that its advocates do not suspend judgment or do so only partially. Only twice in that segment does he mention undisturbedness. The first occurrence is found in the chapter in which Sextus considers whether Cyrenaicism is the same as skepticism: whereas the Cyrenaics say that the aim is pleasure and a smooth motion of the flesh, the Pyrrhonists say that it is undisturbedness (PH i 215). The second occurrence is found in the quoted passage. We are told that Arcesilaus did not adopt undisturbedness as his aim, but it is also clear that this state of mind did not accompany his suspension of judgment about everything, since it is remarked that it is the Pyrrhonists who say so. Now, these differences between Arcesilaus and the Pyrrhonist with respect to undisturbedness do not seem to constitute, in Sextus's eyes, a reason for maintaining that Arcesilaus is not a skeptic. Indeed, such differences are referred to at the very point where Sextus is enumerating the reasons why Arcesilaus's and the skeptic's orientations are almost the same. In this regard, note that the text seems to indicate that the Pyrrhonist, too, regards suspension as one of his aims. It is only in the passage that follows the one quoted that Sextus refers to a possible difference: unlike the skeptic, Arcesilaus is said to have made assertions about the nature of both suspension and assent (PH i 233). Sextus also points out that it is said that Arcesilaus, though apparently a Pyrrhonist, was in reality a dogmatist, because he used his aporetic skill to test whether his companions were fitted to receive the Platonic beliefs (PH i 234). Sextus does not put much trust in those accounts of Arcesilaus's stance that depict him as a dogmatist, judging both by his remark that it seems to him that the latter's orientation and the skeptic's are almost one and the same, and by the fact that he does not offer those accounts in propria persona. Such approbation is unusual in the final segment of the Pyrrhonian Outlines-the other unusual case is that of the Methodic doctors at PH i 236-241. Still, Sextus remarks that Arcesilaus's orientation is almost (σχεδόν) identical to that of the Pyrrhonist. One may hypothesize that the reason for such qualification is that, in order to preserve Pyrrhonism's novelty, Sextus refrains from conceding that the stance of a member of the so-called skeptical Academy is one hundred percent the same as that of the Pyrrhonist's. Or one may hypothesize that the reason is found in the typically skeptical caution that Sextus also exhibits regarding Pyrrho when he remarks that 'Pyrrhonian' is one of the appellations of the skeptical orientation 'because of the fact that Pyrrho appears to us to have attached himself to skepticism more tangibly and more conspicuously than his predecessors' (PH i 7). Someone might argue that the reason for such qualification is instead that undisturbedness plays no part in Arcesilaus's philosophy. If that were so, why does Sextus not mention this fact when referring to the possible differences between Arcesilaus's stance and the skeptic's rather than when explain449 ing their similarities? As we saw above, in the case of Cyrenaicism, he explicitly refers to undisturbedness when identifying the differences between this philosophy and Pyrrhonism. But even if we accept that the fact that undisturbedness plays no part in Arcesilaus's philosophy is indeed the reason for Sextus's use of the adverb σχεδόν, the important point for present purposes is that, if both the pursuit and the attainment of undisturbedness were essential to Pyrrhonism, then the difference in question would be central enough to merit the claim that the Arcesilean and Pyrrhonian philosophies are fundamentally different, a claim that Sextus does not make. III. Concluding Remarks I have argued that not only should one come to the conclusion that neither the search for undisturbedness nor its attainment are defining features of Pyrrhonism if one examines this skeptical stance from a systematic standpoint, but that there is textual evidence that supports such an interpretation of Pyrrhonism. At PH i 12 and PH i 25, Sextus makes it clear that the skeptic may abandon undisturbedness as an aim and replace it with a different one without this entailing that he ceases to be a skeptic. For undisturbedness is the causal principle of skepticism in the sense that the desire to attain it happened to motivate the prospective skeptic to engage in philosophical investigation. But he may well have had a different initial motivation, without this implying that anything fundamental is missing inasmuch as the hope of becoming undisturbed is not the main constitutive principle of skepticism. What about the attainment of that state of mind? In my view, AM i 6 and PH i 232 provide evidence not only that Sextus did not regard the search for undisturbedness as essential to Pyrrhonism, but also that it appeared to him that, if after exercising the δύναμις ἀντιθετική the Pyrrhonist did not attain that state of mind, his stance could still be described as skeptical. Thus, the textual evidence in favor of the view that someone can be a Pyrrhonist without adopting undisturbedness as an aim is stronger than the evidence in favor of the view that the attainment of that mental state is not an essential feature of Pyrrhonism. Why can someone be described as a skeptic even if he is not engaged in the search for undisturbedness or does not become undisturbed after suspending judgment? The reason is that neither fact entails the loss of any of the four features that, in my view, define Pyrrhonism: (i) the systematic exercise of the ability to produce oppositions, by means of which the Pyrrhonist takes careful account of both the conflicting views that are, or might be, adopted on a given issue and the arguments in favor of each one of them; (ii) the continuing engagement in open-minded and truth-directed inquiry;16 (iii) the suspension of judg16 I once claimed that engagement in inquiry is not essential to Pyrrhonism (Machuca 2013, 210n14). But this is plainly wrong, since Sextus tells us that the skeptic's ongoing involvement in investigation is what distinguishes his stance from the other two main types of philosophy (PH i 1–4), that 'investigative' is one of the appellations of the skeptical outlook (PH i 7), that suspension is a state of mind that comes about in the skeptic after an investigation he has undertaken (PH i 7), and that suspension results from the equipollence of the matters being investigated (PH i 196). 450 ment that results from the fact that the conflicting views on every topic the Pyrrhonist has so far considered appear to him to be equipollent; and (iv) the adoption of what appears as the Pyrrhonist's criterion of action, which includes as one of its aspects an extensive non-doxastic use of the perceptual and intellectual capacities with which he is naturally (i.e., involuntarily and inescapably) equipped. 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