Empiricism and Philosophy Nathan Sinclair Degree: Doctor of Philosophy The University of Sydney 2008 This thesis is submitted in partial fulfillment for the degree of doctor of philosophy and is entirely my own work except where indicated in the references. 4 To Kate, with and without whom I could not have written this Contents I Evidence 27 1 Strong Empiricism 31 1.0.1 Translation . 32 1.0.2 Postulation . 32 1.0.3 Sense-data . 34 1.1 The refutation of strong empiricism . 37 1.1.1 Craig's theorem . 39 1.1.2 Hidden objects and computational complexity . 44 1.1.3 Another view of hidden objects . 47 2 Weak empiricism 51 2.1 From experience to stimulation: the rejection of phenomenology . 51 2.1.1 Evidence naturalised . 61 2.2 Stimuli . 62 2.2.1 Looking under the skin . 63 2.2.2 Looking at sensory surfaces: Problems with inter-subjective identification of stimuli . 73 2.2.3 Looking above the skin . 75 2.2.4 Each to their own . 92 2.3 The scope of human knowledge according to weak empiricism . 95 2.3.1 Foundations and Constructions . 106 2.3.2 The status of logic . 114 II Inference 117 3 In search of necessity 119 3.1 Conceptual Necessity . 121 4 Quine's arguments against analyticity 147 4.1 Circularity . 148 7 8 CONTENTS 4.2 The first argument from Universal Revisability . 152 4.3 The second argument from Universal Revisability . 153 4.4 The argument via Universal maintainability . 156 4.5 The good argument . 161 4.5.1 Objections and loose ends . 176 4.6 The End of a Dream . 193 III Philosophy 203 5 Distinguishing philosophy and science 207 5.0.1 Causes of Quine's oversight and its acceptance . 209 6 Resolving philosophical disputes 211 6.1 Philosophy of the don't cares . 211 6.1.1 The lack of decisive resolutions . 214 6.1.2 The need for decisive resolutions . 215 6.2 Some traditional suggestions for resolving philosophical disputes 217 6.2.1 Simplicity . 217 6.2.2 Inconsistency . 224 6.3 Looking for a defect other than inconsistency . 227 6.3.1 Theories . 227 6.3.2 Defective Theories: First Impressions . 229 6.3.3 Ambiguities without senses . 232 6.3.4 The fly in the ointment: Craig's theorem revisited . 243 6.4 Conclusion . 248 Introduction We ought not then be lead astray by the contentious argument you quoted. It would make us lazy, and is music in the ears of weaklings. The other doctrine produces energetic seekers after knowledge; and being convinced of its truth, I am ready, with your help, to inquire into the nature of virtue. (Socrates in the Meno) In nineteen ninety-eight I experienced a physical, an emotional and an in- tellectual crisis. I was beaten and stabbed1 four times on Petersham station, I separated from the mother of my first two (and then only) children, and I lost faith in the analytic-synthetic distinction. Though it dominated for a short pe- riod of time, the physical pain soon subsided; and as it gradually became clear that my children were going to largely recover from the harm inflicted upon them in my separation with their mother, so did the emotional. The longest en- during crisis, and the one which over time caused me the greatest unhappiness, was my loss of faith in the analytic-synthetic distinction. The ankle-tap which lead to my rejection of the analytic-synthetic distinction was provided by Michael McDermott in a course titled \Ayer and Quine". That course introduced me to Quine's polemic against the existence of a distinction between analytic and synthetic truths. Till that time I had held a constellation of beliefs that may be best tersely described as a form of Australian realism; and, influenced by David Armstrong, I took Wittgenstein's Tractatus Logico- Philosophicus to be one of the central texts of that school. (At the time I was unaware of the work's latent phenomenalism2) Even at the time the Tractatus was not taken as holy writ; Armstrong held that the atoms into which possible states of affairs could be divided were to be discovered by empirical investiga- tion rather than by analysis of the meanings which were these atom's semantic counterparts. For my own part I held a less rigid view of atoms, believing that 1with a key protruding through the knuckles 2I now have the impression that the only thing stopping Wittgenstein from an open ad- mission that the atomic facts were sensory was, to borrow his term, an inability to make sense of the \grammar" of the phrase `is an atomic fact'. 9 10 CONTENTS like many mathematical spaces, if the space of possible worlds had at least one basis or spanning set of atomic elements then it had at least countably many such sets. Like Armstrong however, I thought that such spanning sets, and hence the range of space that was to be spanned, were to be discovered in the first instance by scientific empirical investigation. My loss of faith in the analytic-synthetic distinction was all the more painful because I had not realised that it had been based upon faith at all. Eventually, after much struggle to find a defence of the distinction, and despite finding many flaws in all the oft-recited arguments against its existence, I came at last to realise that my own belief in the analytic-synthetic distinction had been based upon the cardinal Wittgensteinian sin of presuming that my intuitions came with labels attached. This loss did not occur overnight, nor without much searching about for alternative justifications, and my master's thesis, written in the dying days of my faith, was a disconnected hodge-podge of various attempts to revive the distinction. My final rejection of the distinction came at a high price. Prior to rejecting it I had taken the production of (interesting) valid arguments to be an essential part of philosophical practice, and thought validity to be analyticity of the conditional. I was thus left without any account of why anyone should listen to anything I had to say, nor why I should listen to the pronouncements of others (particularly other philosophers). Scientific theories could still be recognised as having some merit, for they gave issue to predictions that turned out to be palpably correct, (though how this merit might be recognised ahead of time remained a mystery) but it seemed that philosophers had nothing of value to add to scientist's brute practices of modifying their theories in the light of accumulating evidence. Getting the right answer, making predictions that came true was the only standard by which theories were to be judged, and all the rest was suspected of being hot air. Though such a state is not conducive to wide reading, I scanned the liter- ature avidly for any hope of an alternative. Just because I did not have any account of the distinction between good and bad arguments, nor my ability to discern the difference, that did not imply that there was no such distinction to be made. (Concern that my only reason for believing this was an unfounded intuition that the contrary conditional was invalid was put aside for practical purposes.) At one time we were unable to account for the ability of chicken- sexers to discriminate between male and female chicks but chicken-sexers had the ability nonetheless and their exercise of it was a useful and productive en- terprise, though at least in their case there was an account of why it was useful. My investigation into the literature in hopes of an alternative account of the epistemic basis by which the valid arguments of a novel foreign tongue might CONTENTS 11 be identified revealed, to my surprise, that though the rejection of the analytic- synthetic distinction was almost universal and widely heralded, I was almost alone in being troubled by it. In hindsight I believe that this almost universal and curiously undogmatic slumber has two main historical causes: The first is the wide-spread rejection of the very idea of a sharp distinction between sci- ence and philosophy (which in turn is largely due to Quine's arguments that \One effect of abandoning them [i.e. the analytic-synthetic distinction and re- ductionism] is, as we shall see, a blurring of the supposed boundary between speculative metaphysics and natural science"), and the second was Lewis' ac- count of philosophical methodology as the systematisation and simplification of our pre-existing intuitions and the consequent extraordinary popularity of beginning philosophical papers with appeals to intuition. One of the oddities of the historical role of the belief that there is no sharp distinction between science and metaphysics is the extraordinary discrepancy between the arguments which have been taken to justify it, and the conclusions that philosophers have drawn from it. Though the most influential arguments for this belief are Quine's, and are entirely epistemic and based upon empiricist principles, philosophers have used this belief to justify the rankest unempiri- cal metaphysical speculation. Quine's point was that metaphysical speculations were to be judged by the same standard as scientific speculations | i.e. whether they contributed to the development of the simplest and strongest overall em- pirical theory fitting with our experiences. Good metaphysics, like good science, simplifies and clarifies, and bad metaphysics, like bad science, either breaks the fit with experience or pointlessly muddies the waters. The conclusion that many philosophers citing Quine as their authority for this belief appear to have drawn from it however, is that the most unempirical speculation deserves the same respect and credibility as science.