Logos

by Tallis Raymond

  A truly classifying animal – and there seems to be only one of these – is a consciously reclassifying animal that sees items as existing in themselves independently of any class to which they may be allocated. The capacity for reclassification is also evident in the extent to which encounters with items are only loosely connected with patterns of behaviour, in contradistinction to animals where what is called “classification” is defined by elicited behaviour. Our relationship to objects is not defined by a disposition to respond to them in a certain way. Chairs do not automatically elicit sitting behaviour: they may be used to block doors or as weapons (as in so many Westerns); gazed at with pleasure; or put up for sale to realize their value in times of hardship. We use items, yes; but we use them as such-and-such and the “as” reveals an uncommitted space between object and behaviour. The loose connection between classification and action – how we see or interpret things – is a central aspect of our agency and of our inhabiting a world that is at least in part a chest of tools or, less formally, of handles and levers. Genuine tool use is a relationship between a subject and its world that is remote from that between an organism and an array of stimuli. Even where tools and other objects are expropriated to biological ends, the relationship between tool and tool-user, object and object-user, is unlike that seen in the quasi-tool use of animals.38

  It is revealing that Quine actually accepts the independence of classes from the objects that fall under them. Indeed, he goes further – too far, I believe – and assigns them a stand-alone existence. His avowedly physicalist ontology includes “physical objects, plus all the classes of them”.39 We may doubt that classes, which after all are not located in space and time like objects and do not “occur” like events, belong to such an ontology as usually understood. Perhaps we should be grateful for his acknowledgement that classes are not merely the implicit internal accusatives of types of behaviour.

  Quine’s endeavour to provide an account of how we get from sense experience to scientific knowledge is worth examining a little further because, by virtue of what is missing in it, it inadvertently draws attention to a key aspect of the challenge of understanding our sense-making activity.40

  As we have seen, Quine believes that the ultimate source of the body of knowledge and theory that is science is the stimulation of our sensory surfaces. Unfortunately, our theories are cast in propositional form – as are the observation sentences that would provide the link between them and the tribunal of experience. “Neural intake” does not have such a form. There is a gap, therefore, between, sense experiences, understood as Quine understands them as “neural intake” and observation sentences that provide a test for everyday and scientific theories. It is a profound gap that should not be glided over for many reasons. Here are a couple. Firstly, we lack explanation of how we get from particular experiences to general statements. Biological mechanisms such as stimulus generalization do not even deliver common nouns, even less the other parts of speech necessary to cobble together a sentence. Secondly (and linked with this) observation sentences are connected in relations of implication and contradiction which are unknown to neural intake (this is the coherence dimension of scientific, indeed of any propositional, truth). If it is true that Socrates is a man, it cannot be true that he is a goat. If it is true that all men are mortal, Socrates being a man cannot be immortal.

  Quine attempts to close the gap between aconceptual, non-propositional sensations on the one hand and observation sentences that test scientific theories on the other by mobilizing the notion of the “stimulus meaning” of such sentences. Meaning is defined as the neural activity corresponding to a stimulus that would prompt assent to it. I see a bee, and say “There is a bee”. You, who are familiar with the language, think “there is a bee” when I utter this sound. Thus, I communicate to you the fact that there is a “bee”. The connection between the observation sentence whose truth would support a theory and neural intake is a causal one.

  There are surface and deep reasons why this does not work. The surface reason is that there is no simple mapping between a sentence (never mind one advanced with the aim of testing something as complex as a scientific theory) and a pattern of neural discharges. In short, it is impossible to imagine a congruence or isomorphism between what is happening in the observer’s brain when she experiences the sentence as true and what is happening in the brain when that which makes it true is observed. This is evident, even in the case of seemingly basic observations. I am looking out of the window of the café at which I am now writing. There is a busy scene and I observe a couple in deep conversation hurrying past. Nothing plausibly neural would seem to correspond to that which is picked out from the background – from the pavement, from the crowd, from the street – of the couple, the depth of their conversation, and their hurry.

  There will be those who stubbornly adhere to the neural theory of any element of consciousness – so let us move to a deeper reason for rejecting the idea of “stimulus meaning”. They are connected with the illuminating flaws in the causal theory of knowledge. The idea that the relationship between an observation and assent to an observation sentence predicting the observation could be causal would, if true, collapse the complex, many-layered intentionality connecting scientific observations with, on the one hand, the theories which they test, and, on the other, the experience that makes true the sentence capturing that observation. That is why Quine’s aim to reduce epistemology to “an improved understanding of the chains of causation and implication that connect the bombardment of our surfaces, at one extreme, with our scientific output at the other”41 is to bypass pretty well everything that is distinctive about knowledge.

  It also removes the basis for the distinctive power that knowledge, particularly scientific knowledge, confers on us. If knowledge were simply another means by which we were causally wired into nature, it would hardly enable us to operate, as we do, at such a distance from the natural world, so that we can shape nature in accordance with goals that nature does not envisage and in a timeframe that is not evident elsewhere in nature. The extended powers of Homo scientificus would be entirely inexplicable. Closer to home, there would seem to be no place for judgement – of truth or falsity, of validity or non-validity, of observation sentences, never mind higher-order theories.

  What kind of material effect is it that judges its material cause to be true (or false), valid (or invalid)? The effects we are familiar with in the natural world do not hark back to their causes and hardly ascribe truth values to them. And what of the propositions that are so judged? The world does not naturally divide into discrete items corresponding to what is proposed in propositions. Referents are on the far side of a double intentionality – the aboutness of the experience of a heard or read sentence (my hearing what you have just said, or seeing what I am reading), and the aboutness of the token sentence (what the utterance or written sentence meant). The boundaries of those referents, what is more (even when they are singulars such as “the Battle of Hastings”), scarcely correspond to nature, or the physical world, self-carving at the joints. At any rate, the causal theory of knowledge – perhaps the original sin of naturalized epistemology – involves taking the idea of causation to places where it has no right to be.

  What is, perhaps, most fundamentally missing from Quine’s account of the passage from “stimulus to science” is that it overlooks the profound difference between the passive sentience of the recipient of a stimulus and the active sense-making of Homo scientificus. Indeed, this contrast is present at much lower levels in the contrast between (passively received) sense “impressions” and (active, proposing) “propositional awareness”. From a basic level upwards, humans are not merely subject to experiences but actively shaping, organizing, interpreting them and generalizing them so that even experiences that are not directly connected may be sorted according to their putative origins. If Kant overstates the activity of the mind in putting together a world, Quine understates it, in his desire to buil
d an account of our world-picturing out of neural events in which the fundamental mental activity of positing intentional objects is somewhat bypassed – even in his employment of the notion of “reification”. His term “neural intake” overlooks the fact that what is taken in reaches out; the light that gets into the eye is the basis for the gaze that looks out. To reiterate a point made earlier in relation to the lack of a basis for the input-output reference in functionalist and other forms of behaviourism, “intake” would not, simply as part of a causal chain, even count as intake because there would be no basis for the contrast between “in” and “out”. It is the “outreach” that locates the organism as a point of reception and the centre of its world.

  Quine’s attempted rational reconstruction of the journey from stimulus to science, from tingles to theorems, only highlights, therefore, the failure of the larger project of naturalizing knowledge. Ernst Mach’s earlier naturalizing project is, if anything, more ambitious. He spoke of his “profound conviction”: “[t]hat the foundations of science as a whole, and of physics in particular, await their next greatest elucidations from the side of biology, and especially from the analysis of sensations”.42 In some respects, this may seem less radical than Quine, if only because Mach did not seem to be a consistent hard-line physicalist. Indeed, he wasn’t even a hard-line anything-ist. He is often associated with a monism that saw mind and matter as aspects of a single stuff. However, he regarded monism “as provisionally a goal after which we [he and his closest intellectual allies] all strive, but … scarcely anything fixed or sufficient”.43 That goal was in part to be pursued by a Quine-like tracing of the connections between basic sense experiences and scientific theories; between itches and the theory underpinning the pharmacology of treatments for scabies.

  The guiding assumption was also the Quinean one that the world we experience is a construct of the nervous system whose (biological) function is to enable us to respond effectively to a changing world. One aspect of this is that we don’t perceive things directly but rather the relations between the stimuli that are associated with them. This may sound like a Kantian domination of mind in the shaping of the experienced world but it is not; for the mind, according to Mach (as with Quine), is not the manifestation of a transcendent self but the (physical) activity of a brain shaped by evolutionary processes.

  This shaping is evident at a very basic level in a phenomenon associated with Mach’s name: the intensity of changing stimuli is exaggerated while the intensity of constant stimuli is underplayed. Change, novelty and boundaries, are privileged, something that is clearly of adaptive value. New messages are more important than “messages already received”, and occurrent events more important than their standing background. This a priori that shapes experience is emphatically not a Kantian a priori but one formed by experience, being imposed on later experiences by earlier ones. Since it is mediated by the evolutionary process, “earlier experiences” are not confined to the life of the individual organism but have arisen out of the experiences of ancestral organisms forged by the processes of natural selection. For Mach, scientific inquiry is also child of adaptive behaviour guided by adapted perception: “Scientific thought arises out of popular thought, and so completes the continuous series of biological development that begins with the first simple manifestations of life”44 (emphasis added). However, science, as Mach admits, has been “the most superfluous offshoot” of biological and cultural development.45 For the greater part of the history of humanity, power – and the opportunities to replicate one’s genetic material – has hardly lain with those who advance the cognitive capacity of humankind. It has more often been the privilege of the most successful fighters, foragers and predators. Even at a collective level, conquest and triumph have depended more on social organization than cognitive superiority. Science remains a biological mystery to which biological science offers little to help us solve.

  Our cue for a return to Quine’s attempted rational reconstruction of the path between stimulus and science. I have argued that it proposes steps for which there is no clear biological mechanism. The unification of the sensory field into a moment-to-moment proto-world, the metaphysical intuition of enduring, public objects-in-themselves, and the emergence of explicit classes to which items in the experienced world are allocated – none of these seem to yield to a neural or neurobiological explanation. Even if these steps brought biological utility, this would not explain how they are biologically generated.

  It might be argued that there are many evolutionary developments that we cannot even begin to explain. The origin of life, the emergence of multi-cellular organisms, the development of organs such as the eye – these are some of the targets those who wish to cast doubt on the theory of evolution, have fixed on. There is, however, a plausible gradualist story for much of what happens in evolution. By contrast, the passage from insentient mechanisms to conscious behaviour is difficult to account for – at least at its origin – in terms of competitive advantage; and so too is the capacity for the kind of cognitive advance seen in humanity. At any rate, it is impossible to see that kind of advance as being driven by, as well as conferring, biological utility.

  Naturalism therefore does nothing to demystify our extraordinary capacity to comprehend the world by claiming that we are part of that which we understand and that there is consequently no gap between the world that is comprehended and the mind that comprehends it. To makes this idea seem plausible, it is necessary to glide Quine-like over the real discontinuities – such as between stimuli and our large-scale ideas of the world. By the time we have reached scientific theories, we have long ceased to be (just) material objects in a material world or organisms in nature. These discontinuities are evident, as we have seen, at a level far below that of scientific hypotheses about how the world works with their apparently limitless range. Naturalistic accounts of human knowledge are given seeming plausibility only by a confusion between a) demonstrating that something may conceivably have a biological advantage and b) proving it must therefore have been generated by, and is therefore explained by, the kind of processes that gave rise to wings and kidneys. There are many capacities that might confer biological advantage – for example the ability to become entirely immaterial for a period when a predator is circling – but this does not mean that they are there to be requisitioned: their value does not explain their genesis. We should not confuse why science takes the form that it does such that it “works” with the question of why there is science. That potential biological utility is not sufficient as an explanation of a desirable capacity such as this ability to make higher-order sense of the world is evident from the fact that much higher-order sense does not translate – and certainly not directly or immediately – into replicative advantage for the genes of the organisms that are blessed with such sense.46

  There is a more fundamental reason why the naturalization of sense-making – which aims to close the metaphysical gap between that which makes sense and that which it makes sense of – is misguided. It is this: the gap is necessary for the (undeniable) distinction between the two to be maintained. The sense-maker who “faces” the world, and tries to understand it, must be offset from it in a way that is different from the way two pebbles are offset from each other or the separation between an insentient organism and “its” environment. We shall return to this issue, central to the present inquiry, in Chapter 6.

  If we set aside the lens of evolutionary theory and ask whether the very fact we are part of something could help to explain why or how we can make sense of it, we can see the difficulty more plainly. A pebble is not granted insight into matter simply in virtue of being a piece of matter – or of course granted insight into its own nature in virtue of being a pebble. Nor does it have a world. The biological approach to knowledge and understanding that identifies these faculties with neural activity – minute events in a minute part of the universe, scintillations miniscule compared even with our pin-prick heads – does not seem to be
able to accommodate the kind of difference from pebbles that would reveal to the world its own nature. If nerve impulses are understood as physical events, they seem highly unlikely to rise above the small patch that they occupy to view and make sense of a world that vastly outsizes them.

  In short, the very claim that comprehension of the material world is a biological, that is to say a material, part of the material world – and which consequently collapses the gap between knower and known – makes our knowledge of or about that world seem less not more comprehensible. Our being exquisitely tuned to our ecological niches, so that we are square pegs in square holes, hardly explains how it is we make sense of the holes, the pegs, or the world into which the hole is drilled – even less of the universe compared with which our world hardly figures as microscopic patch of light.

  In the present chapter and the last, we have examined two approaches to dissolving the mystery of our making such large sense of the world. They both endeavour to collapse the distance between the mind that does the sense-making and the world that is made sense of. Kantian idealism gathers up the experienced world into the mind. The various forms of naturalized epistemology embed the mind in the natural world: our sense-making capacity is a necessary feature of an organism that has been forged by natural selection.

  Both views are anti-realist in that they accept that what we make sense of is not something “in itself”, entirely independent of our sense-making minds. This is obvious in the case of Kantian transcendental idealism but perhaps less so in the case of evolutionary epistemology. The latter appears to be tough-minded, connecting the sense we make of the world with the conditions under which we qua organism can survive. But the difference is more apparent than real. The world we make sense of is a world in part defined or constructed by our senses. More importantly, it is a world defined by our material needs and the vulnerabilities and opportunities connected with them. It would be going too far to describe evolutionary epistemology as “organic idealism” because much that is relevant to the welfare and fate of the organism is unknown to it – remote from any ideas it might have, even from its experiences, indeed from “mind” even in the broadest sense.47