Monday, 30 July 2007

Naturalising Epistemology: Quine vs. Crumley

Thus far we have established that naturalised epistemology is no longer concerned with providing some justification for science that is prior to science. However, defenders of traditional epistemology point out that this still leaves room for sceptical worries that find their starting place within science. Science, remember, informs us that our theoretical conception of the world is underdetermined by our sensory evidence. Thus, even if we give up first philosophy, Quine still needs to account for the gap between "meagre" input and "torrential" output. Of course Quine can easily account for such a gap in causal terms. That is, science can, at least in principle, provide a complete causal account describing how sensory stimulation is eventually translated into theoretical posits. However, it is not the causal gap between evidence and theory that bothers defenders of traditional epistemology, but rather the inferential gap. In other words, the problem of the underdetermination of theory by evidence amounts to a normative question: what justifies the inferential leap from observation to theory?

There are two possible replies that Quine may wish to advance in response to the inferential gap question. He may simply, and stubbornly, maintain that such questions are no longer relevant once we dispense with first philosophy. However, it is not immediately clear that giving up the quest for a justification of science means that all normative questions regarding inferences are therefore irrelevant. Quine's second option would be to provide a normative description of what justifies our theoretical inferences, but from a naturalistic perspective.

Which of these options Quine himself would opt for is not clear since on separate occasions he seems to make statements suggestive of both possible replies. However, in what follows I will take the second line of response (if only because doing so would make for a much more interesting post). To wit, I will argue in favour of a normative, and yet naturalistic, description of our inferences from evidence to theory. The starting point for just such a normative description is alluded to by Quine himself: "Again there is the area [called] evolutionary epistemology [that] shows how some structural traits of perception could have been predicted from survival value."[Quine (1994), 30]

Defenders of traditional epistemology emphasise that epistemology is not only concerned with which belief forming mechanisms are truth-conducive, but also with why they are truth-conducive. Hence, an adequate naturalistic account of knowledge should provide no less. The naturalistic response to this challenge is an evolutionary epistemology that explains justified belief in terms of natural selection. On this view, nature has endowed us with cognitive mechanisms and epistemic practices that are biased towards truth. The underlying assumption here is that natural selection isolates and preserves those belief-forming mechanisms that are truth-conducive. Creatures with belief forming mechanisms that are generally not truth-conducive fair very poorly in the evolutionary struggle and eventually go extinct. If nature has constructed us so that we are biased towards truth, then the best means at arriving at truth is to use the very cognitive mechanisms nature has given us. Thus, evolutionary epistemology's investigation into our use of induction and our reliance on our perceptual mechanisms turns out to be not merely a descriptive but also a normative endeavour. In brief, had our belief forming mechanisms not been generally truth-conducive (as the sceptic fears) we would not even be around to talk about them.

Jack Crumley raises two objections to the above evolutionary account of epistemic justification. Crumley notes that the evolutionary argument depends on the assumption that natural selection favours mechanisms that are generally truth conducive. However, he points out that false beliefs may often have survival value. For instance, erring on the side of caution may often prove be of greater survival value than an even-handed assessment. To wit, the individual that ran away every time the bush rustled because she assumed that there was a lion in the bushes may fair better than her pathetic, yet epistemically more praiseworthy, companion who sticks around to investigate. Secondly, Crumley notes that it is questionable that many of our scientific beliefs contribute to our survival. Thus, he remarks poignantly: "Nature seems, at best, indifferent to whether we truly believe that quarks have flavours."[Crumley (1999), 203]

In my next post on this topic I will respond to Crumley’s objections.

Jack Crumley, An Introduction to Epistemology. (California: Mayfield Publishing Co., 1999).

Monday, 23 July 2007

Naturalised Epistemology: Quine vs Stroud (Part 2)

In his notoriously laconic reply to Stroud, Quine treats Stroud's dilemma as merely an instantiation of the sceptical worry that reality might be very different from how we perceive it to be. If the first horn of the dilemma, that science is wrong, obtains then it naturally follows that reality is not as we perceive it to be. If the second horn of the dilemma, that all our theories are merely unverifiable posits, obtains then there is no way for us to rule out the possibility that reality is not as we perceive it to be. Both horns of Stroud's dilemma, then, amount to the sceptical worry. I take this conclusion to be uncontroversial, and I will therefore treat a successful reply to the sceptical worry as a successful reply to Stroud's dilemma.

Quine maintains that the meaning of words is determined by their usage within a linguistic community. When we say: "there is a spoon," we are simply referring to a certain set of sensory stimulation’s to which our linguistic community has inter-subjectively applied the label "spoon." Ontological worries regarding the nature of what lies behind sensory stimulation is irrelevant to the relationship between language and these sensory stimulations. In short, what science regards as a "real" spoon is just that inter-subjective set of sensory stimuli:
What then does our overall scientific theory really claim regarding the world? Only that it is somehow so structured as to assure the sequences of stimulations that our theory gives us to expect. More concrete demands are indifferent to our scientific theory itself. (Quine [1981], p. 474).
This does not of course mean that our scientific theories can never be mistaken. However, they will be mistaken precisely in terms of a failure to accurately predict observation. If, however, a scientific theory were to account for all possible observation, in what sense could that theory be described as mistaken? Once this question is viewed within a naturalistic framework, Quine insists that the answer is none. The sceptical worry that reality may be radically different from what we take it to be rests on the assumption that there is some description of objects prior to the scientific description by which the scientific description may be evaluated. However, once we have located epistemology within science such worries become obsolete. If sceptical possibilities do not affect science's ability to predict observation then they are irrelevant. If, on the other hand, a sceptical worry does impact on science's predictive power then that worry does fall under the umbrella of science and its dissolution becomes the task of science.

For a detailed and extended discussion of Quinean naturalised epistemology see Ben Bayer's paper, Varieties of Naturalized Epistemology: Criticism and Alternatives.

Quine, W.V.O., "Reply to Stroud." Midwest Studies in Philosophy vol. VI The Foundations ofAnalytic Philosophy. Edited by Peter A. French et al. Minneapolis MN: Minnesota Press,1981.

Thursday, 19 July 2007

Back in Scotland

I’m finally back in Scotland, after my all too brief Caribbean adventure, and will be submitting my M.Phil dissertation in less than a month. Very exciting times. This is also a sad time since I will soon be saying goodbye to St Andrews. I begin my PhD at Columbia University in September, which I am eagerly looking forward to. And while we’re on the topic of grad school, there is a great discussion over at Philosophy, et cetera on Getting the Most out of Grad School. The post is actually from last month, but it is definitely worth reading (especially for those who will be beginning their graduate studies this Fall).

Friday, 13 July 2007

Naturalised Epistemology: Quine vs. Stroud (Part 1)

The central difference between Quinean naturalised epistemology and traditional epistemology is located in Quine's rejection of first philosophy. Traditional epistemology is involved in the following two-fold task. First, traditional epistemology seeks to identify the regulating criterion for knowledge. Second, it tries to determine, based on this criterion, whether or not we truly have knowledge. This two-fold task is referred to as first philosophy because it is analytically prior to all of our sensory or empirical knowledge. In brief, traditional epistemology attempts to find the epistemic foundation and justification for all scientific knowledge.

Quine believes that traditional epistemology's attempt to find a justification for knowledge outside of or prior to science has either failed or is moribund. Our only remaining hope of finding a validation for science is within science itself. Hence, Quine's now famous (or is that infamous?) declaration:
"Epistemology, or something like it, simply falls into place as a chapter of psychology and hence of natural science. " (Quine [1994] p. 25).
By Quine’s lights, epistemology is like the mariner in Neurath's parable that has to rebuild his ship as he is sailing on it. We can no more attain a pre-theoretical understanding of science than we can get off a ship while already out at sea.

Defenders of the traditional view tend to object to Quine's naturalised epistemology on two grounds: (1) because it is circular and therefore incoherent and (2) because it lacks the normativity central to epistemology. Stroud's "Reply to Quine" draws on both of these objections. Like traditional epistemology, naturalised epistemology seeks to uncover the relationship between observation and theory. This means providing an account of the disparity between the "meagre" sensory input and the "torrential" theoretical output. This difference between meagre input and torrential output suggests that most of our theoretical knowledge is posited rather than given. In normal scientific investigation we are able to compare a subject's output to the actual world and thereby ascertain how accurately it represents the world.

However, Stroud notes that when we attempt to engage in such a scientific analysis reflexively we encounter the following two-horned dilemma. First, if we assume the accuracy of the scientific picture of knowledge, we find ourselves confronted with the conclusion that all our theories are merely posits. This would not be as bad as it sounds if it we were somehow possible to verify whether our theories accurately represent the world or not. However, when we realise that all our means of evaluating our theories are themselves merely theoretical constructions, or so the argument goes, we find ourselves in a vicious circle. The second horn of the dilemma would be to assume that our scientific picture is wrong, in which case we would simply be confirming the sceptic’s worse fears. Either horn of the dilemma appears to present Quine with an unfavourable outcome.

In my next post on this topic I will look at Quine’s reply to Stroud.

For further reading on this debate, see:

Quine, W.V.O., "Epistemology Naturalized." Naturalizing Epistemology. Edited by Hilary Kornblith. Cambridge, MA.: The MIT Press, 1994.

Quine, W.V.O., "Reply to Stroud." Midwest Studies in Philosophy vol. VI The Foundations of Analytic Philosophy. Edited by Peter A. French et al. Minneapolis MN: Minnesota Press, 1981.

Quine, W.V.O., The Roots of Reference. LaSalle, Ill.: Open Court, 1973.

Stroud, Barry, "The Significance of Naturalized Epistemology." Midwest Studies in Philosophy vol. VI The Foundations of Analytic Philosophy. Edited by Peter A. French et al. Minneapolis MN: Minnesota Press, 1981.

Tuesday, 3 July 2007

St Thomas or Bust

I’m heading off to St Thomas to recharge my Caribbean batteries. A son of the sun like myself can spend only so much time in grey Scotland without going completely insane. Since I probably won’t have internet access for the duration of my trip my blog will be going on a brief hiatus. However, I will be back in about two weeks time.

Sam, from over at Philosophy Hurts Your Head, has paid me the compliment of including the Space of Reasons on his top 5 open-minded bloggers list. I feel honoured! I will be posting my list of 5 when I get back.

Until then…