Hume and Human Error Mark Andrew Hooper BA (Hons) A thesis submitted for the degree of Doctor of Philosophy at The University of Queensland in 2014 School of History, Philosophy, Religion & Classics i Abstract This work is entitled Hume and Human Error. My hope is that it may be of interest to at least two groups of readers: first, to those who are interested in understanding the philosophy of David Hume himself, and second, to those who are interested in explaining the human mind and our propensity to go wrong. My primary objective is to explain how Hume can account, or does account, for human error. In this sense, I am concerned with exposition, and exposition of a rather neglected section of an otherwise comprehensive body of Hume scholarship. There is a rich philosophical history of attempts to understand and provide solutions to the problems of error. Within this tradition, Hume’s account of error is particularly interesting because it should be understood in the context of his general strategy to completely redraft traditional concepts (e.g. substance, causation, self, power) in a way that does not rely on any metaphysical assumptions that cannot be justified by experience. Hume’s method, I argue, leads him to reject what I call the “common sense” or “correspondence” theory of error, according to which what it means to have a false belief (for example) is to have a belief that does not properly represent mind-independent facts about an external world. Exactly how, and in what sense, Hume rejects the correspondence theory is quite complicated, and touches on many of the issues at the heart of the New Hume Debate. With this debate in mind, I argue that Hume has a general strategy of redrafting traditional concepts in a way that does not rely on the existence of external objects, and that Hume’s Theory of Error should be understood in accordance with this general strategy. This is not to say that Hume denies that we can speak meaningfully about external objects, nor that he denies the existence of external objects. Rather, I argue that Hume’s Theory of Error should be understood along the same lines as his rejection of the traditional account of substance as substrata. I note, for example, that when Hume rejects the traditional conception of substance it is not because he flat-out denies the possibility that a substratum may exist. In fact, he thinks that we cannot help but believe that external objects exist. Rather, Hume denies the traditional account of substance on the grounds that we never perceive any such thing as a substratum1, and he infers from this conclusion that we must not ordinarily mean by “substance” what the metaphysicians had thought we mean2. But Hume does not stop there. He then goes on to provide an alternative theory of substance3 – one that is explained in terms of perceptions and the relations between them, and one that does not rely on the existence of a substratum. Hume’s theory of error should be understood with this same methodology in mind. First, he rejects the traditional correspondence theory of error on the grounds that we cannot perceive any relationship between perceptions and external objects. This does not mean that he must also deny the existence of external objects, or 1 “We have no idea of substance distinct from a collection of particular qualities…” (T, 16) 2 “…nor have we any other meaning when we talk or reasoning concerning it.” (T, 16) 3 “The idea of substance as well as that of a mode, is nothing but a collection of simple ideas, that are united by the imagination, and have a particular name assigned them, but which we are able to recall, either to ourselves of others, that collection.” (T, 16) ii the possibility of a relationship between perceptions and external objects. It is only the sceptical conclusion that since we do not perceive any such thing, there is no rational argument to make a case either way. But this sceptical conclusion is by no means the end of Hume’s story about error. Hume also proposes a positive theory about error – one that he explains in terms of his naturalistic science of man, and one that he intends to replace the traditional conception that he rejects. With this framework established, the remainder of the thesis then goes on to explore the interesting and difficult issues that arise in the attempt to put forward such a theory. This leads us to consider a series of related and under-explored issues in Hume scholarship, including Hume’s treatment of physiology, his account of normativity in natural belief, his idea of the self as created by the passions, and his conception of certainty. Exploring Hume’s conception of human error allows us to see all of these separate accounts as unified in a different way that has seldom been explored. As a result of Hume’s novel methodology, many difficult questions arise with regard to providing an account of error. Here are just a few: If Hume’s theory of error does not rely on the existence of external objects, how can he explain what it means to be fooled by an optical illusion? Surely when we call something an “illusion” what we mean is that the way things seem is different from the way things are. How can Hume help himself to this sort of distinction? Why, if Hume thinks that perceptions are all we can know, does he appeal to physiology as a means to explain how errors of association arise? Given that Hume rejects the traditional conception of the self, how can he possibly explain the activity and agency involved in error? Errors don’t simply occur; errors are made by agents who could and should have done otherwise. In other words, we think of error as a normative notion. If Hume rejects the idea of the self as an active and unified substance, how can he account for the agency without which an explanation of error would appear impossible? Does Hume think that any if our beliefs are immune to error? Are we certain of anything? At some points he suggests that relations of ideas (for example simple mathematical truths) are absolutely certain, but at other times he says that all knowledge resolves into mere probability. By examining Hume’s own body of work, and by discussing this work in the context of the tradition to which Hume responds, I attempt to resolve all of these questions, and others. Of course, there are many different kinds of errors, and I do not attempt to provide an account of all of them. I do, however, strive to provide a sort of general framework by which all errors, on Hume’s view, might be explained. iii Ultimately, for all its difficulties, I argue that Hume can indeed provide a very rich and fruitful account of error in his own naturalistic terms. According to this account, error must always be explained in terms of the features of perceptions themselves and the relations between them. If we want to know what any particular error involves, we must ask about the observable conditions that tend to accompany those errors, or how those errors “strike the mind”. Hume’s is a naturalistic theory of error which, like that of the Epicureans, locates error at the level of judgement rather than immediate sensation. But unlike the Epicurean tradition, Hume’s conception of judgment is not explained as the function of a free will or even as the product of an independent mental faculty, but rather as the outcome of the naturally occurring laws that govern perceptions. The pressure to avoid error is also naturalised – it comes from the tendency of creatures like us to avoid the cognitive dissonance that arises from incoherence or contradiction. For those who want a more robust or absolute sense of error, Hume’s account may well prove unsatisfying, but Hume’s is one of the earliest attempts to demystify error – to rid it of metaphysical assumptions – and so it is interesting and important for that reason, if for no other. iv Declaration by author This thesis is composed of my original work, and contains no material previously published or written by another person except where due reference has been made in the text. I have clearly stated the contribution by others to jointly-authored works that I have included in my thesis. I have clearly stated the contribution of others to my thesis as a whole, including statistical assistance, survey design, data analysis, significant technical procedures, professional editorial advice, and any other original research work used or reported in my thesis. 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