Nagels Bat Argument - Essay Example

Nagel’s Bat Argument In Thomas Nagel’s seminal “What Is It Like To Be A Bat?”i he presents a now widely recognized challenge to the thesis of physicalism. In the piece, he points to the phenomenal experience of a bat and that to understand its subjective experience we must have something in common with its sensory devices. The present analysis of Nagel’s main points hopes only to reconstruct and support this claim by raising a couple of challenges. Nevertheless, our defence will fall short of demonstrating the clarity and validity of an alleged “anti-physicalist” conclusion. This shortcoming in Nagel’s argument comes as a result of a conceptual error regarding the nature of a mind-independent, or objective, phenomenon. I. Subjective Character of Experience The nature of phenomenal experience can be illustrated with a thought experiment. A scientist can apply artificial impulses to a subject’s cerebrum through electrodes, causing the subject to react in predicable ways: moving his arm, yelling loudly, and so on. These artificial inputs mirror exactly the natural functioning of the brain. Imagine then if the scientist simulates pain, evoking the appropriate physiological responses, but hears no reports of pain from the subject. For pain to exist, we might conclude, there is a necessary condition that there be first­-hand, phenomenal experience of such. Even though the physiological responses to pain appear, there is still the lack of subjectivity, which proves necessary for the ontic existence of pain. Nagel uses the term “subjective character of experience” to denote the thought that a point-of-view is essentially a set the sum of a thing’s subjective phenomena. The notion of the subjective character of experience suggests, according to Nagel, that some kinds of facts, namely the means by which mental states arise from physical ones, are outside of the realm of human experience and thus unknowable. A bat, for instance, perceives its environment entirely different from how a human being would and given that there is something that the bat subjectively experiences there seems to be some ontological closure for the human mind to some facts. II. A Formulation of Nagel’s Argument The bat forms a particularly effective tool for Nagel to illustrate his claim insofar as that species employs a sensory device of sonar, which is a radically different from man’s means of perception. While any conscious animal would do, the bat’s sensory tools are clearly different in every respect of its operation from sight or any of the other human senses. While clearly conscious, the bat has its own very special subjective character of experience. And because its point-of-view is so incommensurable with man’s, man is closed from understanding the facts of a bat’s phenomenal experience. Breaking Nagel’s bat argument down into its logical form, we might find something like the following: 1. If an organism, O, lacks a bat’s special sensory device, then O does not have a bat’s special subjective character of experience 2. If an organism, P, lacks a bat’s subjective character of experience, then P cannot have access to a bat’s phenomenal experiences 3. Thus, O or P cannot have access to a bat’s phenomenal experiences 4. Human being, Q, lacks a bat’s special sensory device 5. Thus, Q cannot have access to a bat’s phenomenal experiences III. Two Potential Challenges On its face, Nagel’s bat argument seems compelling. And yet we have yet to encounter anything substantively approaching the topic of physicalism, and not just the epistemic status of phenomenon. We move to examine two potential challenges to the argument at hand, and respond to them by clarifying what we mean exactly when we refer to “being like a bat”. Argument from Transformation An argument directed at Nagel’s third premise might be read as the possibility of a biological transformation: the physiological transformation of a human sensory system into that of a bat. However, this unlikely possibility can lead to two outcomes. Either human being, Q, knows what it is like for a bat to be a bat, or bat, R, knows what it is like for a bat to be a bat. It seems, however, that at each stage of one’s transformation, one will still be extrapolating to the next stage. In the middle of this transition, the man/bat knows what it is like for a bat to be a bat. However, where this leaves us is not where we want to be, namely a position in which a human person, and not a man/bat, knows what it is like for a bat to be a bat. Argument from Simulation If we are ambitious enough, we might challenge Nagel again on the third premise: that by using our scientific knowledge, we can simulate, or imagine, to a reasonable degree of accuracy a bat-like experience. In other words, we can know by virtue of having third-person knowledge, what it is like to have subjective bat-experiences. We can conceive of, for instance, how a bat might fly and detect its prey, just as one can imagine how a horse or pig feels at any given time. As potent as this challenge may seem, it mistakes the sense in which Nagel is speaking of the bat’s phenomenal experience. When a human being imagines, it corresponds only to how a bat acts, and not to what it is like to be a bat. This manoeuvres around the issue. When we imagine the bat’s experience, we are confined to the limits of the human mind. It is, by its nature, incapable of appending any other kind of experience not inherent to it. To suggest otherwise would be equivalent to saying that by characteristically acting like a chimpanzee, it is automatically the case that we think like one too. IV. Nagel’s Anti-physicalism Taking Nagel’s argument for what it is, we can begin to see its anti-physicalist tenor. Of course, it is quite clear how Nagel succeeds in showing the cognitive closure of the human mind, but what remains unclear is how this relates to the thesis of physicalism. What the bat argument is directed at, still, is challenging an important premise of physicalism: that we can give a physical description of what it is like to be a bat. Nevertheless, there is a distinction between knowing something in general and knowing something in specific. We can, after all, know what being human is like without a full physical description. Thus, it falls to Nagel to prove whether a physical description is a necessary condition of knowing what it is like to be a bat. It is essential for Nagel to look at the difference between a physical description and knowing what it is like to be a bat in general. If physicalism is likewise to succeed, it cannot exclude the phenomena of our experience, and must provide a physical account of them as well. It is impossible simply to reduce them as one might reduce the chemical molecule to its constituent atoms. Physicalism must do this along with its scientific reductionist commitments in chemistry and biology. In addition to physicalism’s metaphysical commitments, it is also committed to the principle that given the theory’s truth that all things are physical, knowledge about everything physical entails knowledge about all things. Thus, if we are to acquire a comprehensive, full physical description of the bat, such would entail knowledge of what it is like to be a bat in general. Nevertheless, Nagel’s anti-physicalist bat argument stands to say given the fact that the subject is not a man/bat, and is incapable of being two completely different beings at once, is incapable of knowing such facts about the experience of bats, even if he has a full physical knowledge of them. Breaking this argument down, we should find the following premises: 1. If physicalism is true, then human being, Q, with a full physical description of bat, R, knows everything about bats 2. If Q knows everything about bats, then he knows what it is like to be a bat 3. Q cannot know what it is like to be a bat 4. Thus, Q cannot know everything about bats 5. Thus, physicalism is false Of course, the third premise is derived from the conclusion of the previously given bat argument in which Nagel proved that Q cannot know what it is like to be a bat, R. The conclusion of Nagel’s anti-physicalist argument seems sound based on the premises given here. But let us move to consider briefly some possible challenges to this line of reasoning. V. A Challenge to the Argument Certainly subjectivity does not provide the proper basis for a reasonable challenge to the physicalist thesis. We can merely discover that there is a subjective factor in our phenomenal experience, not what the nature of such a factor is. Nagel’s arguments, in fact, rest on his own definitions with regard to the distinction between subjective and objective. Whereas the objective is independent of all conscious perceiving organisms, the subjective comes from within a certain species. However, it seems as though Nagel’s characterization of “objective”, or with mind-independent phenomenon, is mistaken insofar as it is impossible by definition. Objectivity must include the content of experience. The attributing of a subjective character to phenomenal experience is ultimately fixed to the differences in sensory devices between members of species. Because bats and humans possess dissimilarly designed systems for perceiving the world, their respective sensations are subjective insofar as they are dependent on the point-of-view of the species. In contrast, an “objective” character of the world would be something independent of the senses, perhaps with a measuring device. Unfortunately, however, even instruments must be designed, built, and calibrated by living beings, capable only of subjective experiences, thus making even sense-independent measurements incapable of “objectivity” on Nagel’s criterion. Although the use of such instruments help move us away from strictly subjective experience, it makes no sense to say that it is separable into a different kind of phenomenon, based on the distinction between objective and subjective experience. Note that this does not mean that everything is subjective. It only means that Nagel’s argument rests on a conceptual error with regard to both objectivity and subjectivity. Instead of placing objectivity beyond the species, it must be made, on my view, in terms of the space-time-causal network. Instead of describing an object with phenomenal experiences, we do so within the framework of science: removing the observer from the equation to explain the nature of the subject of our inquiry, along with its structure and behaviours. Physicalism, of course, does not aim to replace the subjective (or first-person) with an equivalent objective (or third-person). It merely aims to ground experience in what is physically analyzable and describable, and demonstrate that experience is a natural phenomenon. Thus, despite the fact that human beings will never perceive directly the world in the same way a bat does, this should not be taken to mean that a bat’s, a human’s, or any other organism’s phenomenal experience transcend the possibility of inquiry. Nagel’s anti-physicalist argument, taken in this context, seems to lose its significance to its opponents. This leaves us with nothing but the bat argument, which very few would find controversial. Nagel broaches the topic of objective/subjective, but ultimately fails to make the correct conclusion. What he accomplishes, however, is drawing attention to fixing the gaping hole. The solution proposed here looks at subjectivity in experience as the act of having the experience, which is capable of being scrutinized in terms friendly to physicalism. Additionally, objectivity in experience consists of structural and behavioural properties of the experience. Certainly, a meta-analysis of this “objective experience” is no doubt possible within the physicalist framework. VI. Conclusions Nagel, in constructing his arguments for “What Is It Like To Be A Bat?”, provides a solid account of why we can never hope to share subjective experiences between members of different species. Accordingly, a member of the human species cannot have the phenomenal experience of members of other species, due to the latter’s unique point-of-view and the subjective character of experience. This is of course due to different physiological factors that go into the structure and functioning of sensory systems. However, Nagel goes too far in deriving from these considerations that objectivity, or mind-independence, in his account of experience is achievable. A physicalist account of objectivity rescues the theory from Nagel’s unsuccessful attempts to advance his anti-physicalist reasonings. Read More