17 Nov 2016

Uexküll’s Theory of Meaning, entry directory


by Corry Shores


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Jakob von Uexküll


Theory of Meaning



2. The Meaning-Carrier [Bedeutungsträger]








Uexküll, Jakob von. 1940. Bedeutungslehre. Leipzig: Barth.


Uexküll, Jakob von. 1982. The Theory of Meaning. In Semiotica: Journal of the International Association for Semiotic Studies, 42(1), pp.25–82. Translated by Barry Stone and Herbert Wiener.


Uexküll, Jakob von. 2010. A Theory of Meaning. In A Foray into the Worlds of Animals and Humans, with A Theory of Meaning. Translated by Joseph D. O’Neil. London/Minneapolis, Minn.: University of Minnesota Press.



Jakob von Uexküll, entry directory


by Corry Shores


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Theoretical Biology


Uexküll, Theoretical Biology, entry directory




A Stroll through the Worlds of Animals and Men: A Picture Book of Invisible Worlds


Uexküll’s Stroll through the Worlds of Animals and Men, entry directory




The Theory of Meaning


Uexküll, The Theory of Meaning, entry directory





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Nagel, “What Is It Like to Be a Bat?”, summary


by Corry Shores


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[The following is summary. All boldface in quotations is my own. My commentary is in brackets. Page citations give the 1974 article version first and the 1979 book version second. I apologize in advance for any distracting typos, because proofreading is incomplete.]





Summary of


Thomas Nagel


“What Is It Like to Be a Bat?”




Brief summary:

One central problematic obstacle for working on the mind-body problem is that the mental part involves subjective experience, which takes a first-person point of view that is hard to treat in an objective fashion (and thus it is hard to relate it to the body, which is objectively studiable, along with the world of objects being perceived). This is particularly a problem for reductionist approaches that try to explain mental events either as being no more than physical events, as in physicalism, or that simply ignore all subjective aspects of experience in favor of purely objective descriptions of outwardly apparent behavior, as in behaviorism. We see the problem regarding studying experience, which is subjective, when we note that we can know with certainty that other very different species like bats have experiences of the same objects we do, and yet we cannot know what it is like for them to have those experiences; and thus we do not in the first place have as a basis a subjective experience to reduce or describe objectively. Both we and the bat can perceive the topological features of a cave wall. But the bat uses sonar and we, vision. These are so different that we do not know what it is like to be a bat having this experience. So although the objects we perceive are objectively given, the bat’s experience, which is what is in question, is not available for our understanding. (Yet, when species’ or creatures’ modes of experience are of the same type, then they would be able understand what it is like to be the other having some experience.) Even knowing everything about how the bat’s brain works when it is having an experience does not tell us what it is like for the bat subjectively from its point of view and with its anatomy to have that experience. The main problem with reductions of mental life is that the thing to be studied, experience, is something whose essential character is not accessible to an objective sort of knowledge, which is what these reductions aim to reduce it to. This does not necessarily mean however that a physicalist reduction of mind to body is false, as it is a coherent theory, and we might simply need to find the proper physical processes that give us access to subjective beings-like. But the main problem is that as a reductionist theory, its basic claim takes the form of ‘X is Y’ (mental events are physical events), and although we know what the X and the Y refer to, we cannot know how these terms might referentially converge on the same real observable thing. For, mind and body are such very different things that we do not know yet what sorts of objects or events can be said to be both. Nonetheless, Nagel leaves open the possibility that an “objective phenomenology” might be invented which could somehow overcome this limitation. We do not now know how it might do so, but were it to be created, it would allow us on the basis of an objective account of another species’ experiences to know what it is like to be that creature having that experience. This objective account would not rely on imagination or empathy, which are unable to access very different creatures’ beings-like. It also would not be based on intermodal analogies, like the classic “Red is like the sound of a trumpet” used to describe color to a blind person, as this falls very short of fully capturing all the important experiential features of seeing red. Instead, it would be some sort of description that somehow conveys the structural features of the perception from the creature’s own subjective experiential point of view.






[The fact that consciousness is a real thing makes resolving the mind-body problem difficult, because it causes the reductionist simplifications to fail.]


Nagel claims that consciousness is what makes the mind-body problem so difficult to resolve. [He does not yet explain why, but it seems the idea is that] many thinkers of the time have been trying to reduce consciousness to some other substrate: “The recent wave of reductionist euphoria has produced several analyses of mental phenomena and mental concepts designed to explain the possibility of some variety of materialism, psychophysical identification, or reduction” (Nagel 435/165). But these solutions have their own problems, and they ignore what makes the mind-body problem unique (435/165).





[Reductionist approaches often use analogies to explain the mind-brain relation, but they fail to explain the physical nature of mental phenomena, which is something that reductionist theories fail at more generally.]


Nagel says that reductionists often use an analogy from modern science to help portray the relation of mind to brain, but Nagel thinks that these attempts do not do very well for that purpose (435/166). Philosophers also have overlooked the important features of consciousness by trying to simplify what is hard to grasp about it into more familiar notions (435/166). Nagel will show why these analogies fail and also why we have no satisfactory “conception of what an explanation of the physical nature of a mental phenomenon would be” (435-436/166). He continues,

Without consciousness the mind-body problem would be much less interesting. With consciousness it seems hopeless. The most important and characteristic feature of conscious mental phenomena is very poorly understood. Most reductionist theories do not even try to explain it. And careful examination will show that no currently available concept of reduction is applicable to it. Perhaps a new theoretical form can be devised for the purpose, but such a solution, if it exists, lies in the distant intellectual future.

(Nagel 436/166).





[But we know that conscious experience is something real at least in humans, as we have direct evidence of it in our own mental lives. It might also be something that animals have, and perhaps even simple organisms to some degree. Furthermore, for an organism to have conscious mental states means that there is something that it is like to be that organism.]


[Nagel then switches from the notion of consciousness to conscious experience. Perhaps the difference in emphasis here is between consciousness as some entity in the world with consciousness as something you or I know experientially with direct evidence.] He says that conscious experience is something widespread, existing in many animals and maybe even in simpler organisms. However, we do not know exactly “what in general provides evidence for it”, and so some think that we can only find it in humans [as we have no evidence for it in other creatures or perhaps because we have evidence that it does not exist in other creatures.] Nagel also thinks it can be found in alien life. [Nagel then characterizes conscious experience as involving “being like” the particular organism that has that conscious experience. An interesting point here is that conscious experience is not understood in this respect as a relation with the phenomenal world or the givenness of the world to our awareness or something like that. Instead, conscious experience is understood as something with distinct and perhaps unique qualitative feels. This is perhaps something in lines with Peirce’s notion of phenomenal Firstness (see the relevant sections here). So here, although we are dealing “conscious mental states”, we are not in this sense of “being like” concerned primarily with a sort of awareness or an intentional consciousness. Instead, we are concerned with the qualitative feature of experience which can be said to characterize that experience or more generally a species’ particular modes of experience. Perhaps this distinction has something to do with the fact that Nagel is speaking of “conscious mental states” rather than acts of consciousness.]

Conscious experience is a widespread phenomenon. It occurs at many levels of animal life, though we cannot be sure of its presence in the simpler organisms, and it is very difficult to say in general what provides evidence of it. (Some extremists have been prepared to deny it even of mammals other than man.) No doubt it occurs in countless forms totally unimaginable to us, on other planets in other solar systems throughout the universe. But no matter how the form may vary, the fact that an organism has conscious experience at all means, basically, that there is something it is like to be that organism. There may be further implications about the form of the experience; there may even (though I doubt it) be implications about the behavior of the organism. But fundamentally an organism has conscious mental states if and only if there is something that it is like to be that organism – something it is like for the organism.






[This ‘what it is like to be the organism’ is also called the “subjective character of experience”. Reductionist theories do not even have such a concept to begin with, so they fail to explain how subjective consciousness can be reduced to something else.]


Nagel calls this ‘something that it is like to be some certain organism’ the “subjective character of experience” (436/166). He says that this subjective character of experience is not grasped in the current reductive treatments of mental life, because “all them are logically compatible with its absence” (436/166). [The idea here might be that none of the reductive explanations necessitate there being a subjective character of experience, perhaps because they only look at mental events objectively like physical things in the world. Thus there would be no contradiction if to these theories we added the claim that there is no such thing as a subjective character of experience, because they neither say nor imply anything about the existence of such a thing.] Nagel then says that the subjective character of experience cannot be analyzed in terms of functional states or intentional states, because robots can be said to have such states even though they would not have any experience. [I am not sure exactly what these states are. A functional state might be something like the way something is reacting to inputs of some kind, and an intentional state might be the directness of something’s behavior or inner states toward something else, but I am not sure. The idea here seems to be that a machine can be programmed so that it appears to have subjective conscious states, given the way that it interacts with the world, when really everything about it is perfectly object-like and in no sense is it something with subjective experience. Since the notion of functional state and even intentional state can adequately explain such a machine’s behavior only in a purely objective way, while that machine in fact does not have any subjective experience anyway, means that these notions are not capable of explaining subjective conscious experience.] He next adds that the subjective character of experience “is not analyzable in terms of the causal role of experiences in relation to typical human behavior – | for similar reasons” (436|437 / 167). [I am again not sure what is meant here. He might be saying that we cannot understand subjective conscious experience if we only look at the way that something’s experiences (perhaps described objectively) cause certain (outwardly visible) behaviors.] Nagel emphasizes that he does not reject the notion that conscious mental states and events can cause behaviors, and he also does not reject the notion that we can use a functional sort of characterization of mental states and events (437/167). He simply is claiming that we cannot exhaust the notion of mental states and events with these notions (437/167). His main criticism here of reductionist approaches to explaining the subjective character of consciousness is that they do not even form a concept for it, and thus we would not even know how these theories can be used to explain what it is. [At this point Nagel is assuming that such things do exist. Perhaps those taking these reductionist approaches might even claim that there is no such thing as the subjective character of consciousness. Maybe Nagel’s point would be that still you would need to explain how on the basis of the limited concepts in these approaches we would explain the illusion of our subjective consciousness, when these theories do not even have a concept of it to begin with. Furthermore, these theories want to say that subjective consciousness can be reduced to something else, like physical states and events. But even then, in order for the theory to say that the first thing is reducible to the second, there needs to be concept of the first thing, which is lacking in these theories.]

Any reductionist program has to be based on an analysis of what is to be reduced. If the analysis leaves something out, the problem will be falsely posed. It is useless to base the defense of materialism on any analysis of mental phenomena that fails to deal explicitly with their subjective character. For there is no reason to suppose that a reduction which seems plausible when no attempt is made to account for consciousness can be extended to include consciousness. Without some idea, therefore, of what the subjective character of experience is, we cannot know what is required of physicalist theory.






[A physicalist (and thus reductionist) theory of mental states would need to provide a physical account of phenomenological features of subjective experience. But it cannot do so, as it takes an objective view which is as if it sees the thing in question from any view, while subjective consciousness always has one singular limited point of view.]


[Nagel’s next point might be the following. Suppose we have some physical substance, and our perception of it provides certain phenomenological features, like its color for example. We might be able to give a physical or chemical reductionist account of the substance which does not include these phenomenal features but that instead explains these phenomenal qualities as the results of how the substance’s physical and chemical properties have some effect on the mind of the person observing it. Nagel says that for explaining subjective consciousness, such a strategy would not work. This is presumably because it is not a question of explaining how something outside our mind does not have phenomenal features but rather how our very own mind, as we experience it ourselves from the inside, does not have them.]

While an account of the physical basis of mind must explain many things, this appears to be the most difficult. It is impos­sible to exclude the phenomenological features of experience from a reduction in the same way that one excludes the phenomenal features of an ordinary substance from a physical or chemical reduction of it – namely, by explaining them as effects on the minds of human observers.


Nagel says that someone who defends physicalism must provide a physical account of the phenomenological features of subjective conscious experience. The main reason physicalists cannot do this is because their explanations always take an objective point of view, but phenomenological features of conscious experience always has a particular (subjective) point of view.

If physicalism is to be defended, the phenomenological features must themselves be given a physical account. But when we examine their subjective character it seems that such a result is impossible. The reason is that every subjective phenomenon is essentially connected with a single point of view, and it seems inevitable that an objective, physical theory will abandon that point of view.






[To grasp the notion of phenomenal being-like, we need to not limit our conception to one based on the subject-object distinction. For, our concern is simply with subjective phenomenal consciousness. Nagel first will examine an example that will show the divergence between subjective and objective understandings of the situation.]


Nagel now will state the problem without using the notions of the subject-object relation or the relation between the for-itself and the in-itself. He says this is difficult and that “Facts about what it is like to be an X are very peculiar, so peculiar that some may be inclined to doubt their reality, or the significance of claims about them” (437/168). [Perhaps the point he just made is the following. Our account of subjective phenomenal qualities is limited by the notion of the subject-0bject relation. I do not know the exact reason why, but it might be because this relation is not what is really at the basis of subjective qualitative experience, as the objective side of it is not what is under examination. But giving an account of subjective phenomenal qualities is not easy, on account of the peculiarity of the facts of being-like; in other words, perhaps, my being-like could be so peculiar as to not even be communicable in an objective or intersubjective way, and thus any statements made about one’s being-like could be useless. Please consult the text.]. Nagel will now “illustrate the connexion between | subjectivity and a point of view” and he will also “make evident the importance of subjective features” (437|438 / 168). To do so, he will examine an example that clearly shows the “divergence between the two types of conception, subjective and objective” (438/168).





[The example he will use to show the divergence between subjective and objective conceptions of experience is the phenomenal being-like of a bat. It is similar enough to us that we know it has experience, but it is alien enough that their being-like is hard for us to know.]


His example will be the experience of bats. As a species, they are similar enough to our own that we can say they have experience. But their perceptual apparatus is so different from ours that we can also say their mode of experience is quite alien to our own (438/168).

I assume we all believe that bats have experience. After all, they are mammals, and there is no more doubt that they have experience than that mice or pigeons or whales have experience. I have chosen bats instead of wasps or flounders because if one travels too far down the phylogenetic tree, people gradually shed their faith that there is experience there at all. Bats, although more closely related to us than those other species, nevertheless present a range of activity and a sensory apparatus so different from ours that the problem I want to pose is exceptionally vivid (though it certainly could be raised with other species). Even without the benefit of philosophical reflection, anyone who has spent some time in an enclosed space with an excited bat knows what it is to encounter a fundamentally alien form of life.





[What makes bat perception so alien to our own is that they perceive space and spatial objects by means of sonar. We should see what methods might exist to understand this mode of experience.]


We say that bats have experience because we think that there is something that it is like to be a bat (168). One important aspect of a bat’s being-like is that it perceives spatial objects and distances by means of echolocation or sonar. But sonar is very different from human perception of space and spatial objects, as we use our vision. So we need to see if we can understand the inner life of a bat on the basis of our own inner life, and if there is no such means, we should seek an alternative method to understand their inner life (438/168-169)

I have said that the essence of the belief that bats have experience is that there is something that it is like to be a bat. Now we know that most bats (the microchiroptera, to be precise) perceive the external world primarily by sonar, or echolocation, detecting the reflections, from objects within range, of their own rapid, subtly modulated, high-frequency shrieks. Their brains are designed to correlate the outgoing impulses with the subsequent echoes, and the information thus acquired enables bats to make precise discriminations of distance, size, shape, motion, and texture comparable to those we make by vision. But bat sonar, though clearly a form of perception, is not similar in its operation to any sense that we possess, and there is no reason to suppose that it is subjectively like anything we can experience or imagine. This appears to create difficulties for the notion of what it is like to be a bat. We must consider whether any method will permit us to extrapolate || to the inner life of the bat from our own case, and if not, what alternative methods there may be for understanding the notion.

(438 / 168||169)




[Because our imagination is limited to working on the basis of our own modes of experience, we cannot imagine what it is like to be a bat. For, the features of the bat’s anatomy relevant to its modes of perception and activity are too different from our own for us to be able to imagine its inner life.]



[One might say that despite the differences between our experience and bats’, we can still imagine what it is like to be a bat by trying to imagine ourselves sharing the biological features that affect the way they experience the world.] Whatever we can imagine will be based on the features and limitations of our own experience. So were we to imagine us having all the biological features of a bat that are relevant to the bat’s modes of experience, that does not tell us what it is like to be a bat but rather what it would be like for us to be a bat. But the question is, rather, what is it like for a bat to be a bat? We cannot imagine the bat’s subjective experience by using our imagination either to add features to our own modes of experience [perhaps because those bat-like features that we might add are not already in our experiential vocabulary, namely, we never have nor can we ever use sound in much the same way to perceive the spatial traits of the world], to subtract features from our own modes of experience [perhaps because the bat’s sonar perception is not a deprivation of our own modes of experience but is rather something different altogether], or to make some combination of additions, subtractions, and modifications to our experience (439/169). [I am not exactly sure why the combination does not work, and I am also not sure what is meant by a modification, if it means something other than adding or subtracting to what we already know. Perhaps it would be changing the features of our experience by degrees of variation rather than but cutting off elements or adding entirely new ones. And perhaps the combination does not work because we already said that additions and subtractions alone do not work, and so by combining them we still cannot arrive upon the foreign elements. Let me quote.]

Our own experience provides the basic material for our imagination, whose range is therefore limited. It will not help to try to imagine that one has webbing on one’s arms, which enables one to fly around at dusk and dawn catching insects in one's mouth; that one has very poor vision, and perceives the surrounding world by a system of reflected high-frequency sound signals; and that one spends the day hanging upside down by one’s feet in an attic. Insofar as I can imagine this (which is not very far), it tells me only what it would be like for me to behave as a bat behaves. But that is not the question. I want to know what it is like for a bat to be a bat. Yet if I try to imagine this, I am restricted to the resources of my own mind, and those resources are inadequate to the task. I cannot perform it either by imagining additions to my present experience, or by imagining segments gradually subtracted from it, or by imagining some combination of additions, subtractions, and modifications.






[It also does not help to hypothetically suppose that we have the same cerebral physiology of a bat, because we would actually need to have it in order to know how it would affect our modes of experience.]


Thus, so long as we do not alter our [anatomical] structures, we cannot know what it is like to be a bat. [The next point seems to be the following. We just noted that we lack certain anatomical features related to parts of the body, minus the brain structure. But we also cannot suppose hypothetically that we have the same brain structure and still know what it is like to be a bat. The reason for this might be that those actual changes would need to happen for us to know what it is like to have the bat’s experience from a purely cognitive perspective. Let me quote to be sure.]

To the extent that I could look and behave like a wasp or a bat without changing my fundamental structure, my experiences would not be anything like the experiences of those animals. On the other hand, it is doubtful that any meaning can be attached to the supposition that I should possess the internal neurophysiological constitution of a bat. Even if I could by gradual degrees be transformed into a bat, nothing in my present constitution enables me to imagine what the experiences of such a future stage of myself thus metamorphosed would be like. The best evidence would come from the experiences of bats, if we only knew what they were like.






[So any attempt to understand a very different animal species’ being-like will never be a complete understanding. We might know that they experience things in some particular way, but we do not know what it is like to have those experiences.]


Thus whenever we try to understand the bat’s experience on the basis of our own, it will be an incomplete account. We might know that the bat uses sonar for three-dimensional spatial perception, but we do not know what the subjective character is for having such a mode of perception. There would be even less of a basis to know what it is like to be an alien life from another planet.

So if extrapolation from our own case is involved in the idea of what it is like to be a bat, the extrapolation must be incompletable. We cannot form more than a schematic conception of what it is like. For example, we may ascribe general types of experience on the basis of the animal’s structure and behavior. Thus we describe bat sonar as a form of three-dimensional forward perception; we believe that bats feel some versions of pain, fear, hunger, and lust, and that they have other, more familiar types || of perception besides sonar. But we believe that these experiences also have in each case a specific subjective character, which it is beyond our ability to conceive. And if there is conscious life else-|where in the universe, it is likely that some of it will not be describable even in the most general experiential terms available to us. (The problem is not confined to exotic cases, however, for it exists between one person and another. The subjective character of the experience of a person deaf and blind from birth is not accessible to me, for example, nor presumably is mine to him. This does not prevent us each from believing that the other’s experience has such a subjective character.)

(439|440 / 169||170)





[Just as animals or aliens should not doubt that there is something that it is like to be human, simply because they are too different to know it, so too should we not be skeptical that bats and aliens have their own being-likes.]


Some might doubt that bats can have certain experiential features that we have no access to. But we can imagine an intelligent alien creature being unable to know what it is like to be a human. They should not for that reason be skeptical that there is something that it is like to be human. Thus we as humans should not say that neither bats nor intelligent aliens have no being-likes (440-441 / 170-171).




[There are facts that, given enough time, humanity will be able to represent. But there are other facts that no matter how much time humans have, they will never be able to represent or comprehend them. Such facts are those of subjective points of view of creatures who are very different from us with respect to the way they experience things.]


Nagel then distinguishes between facts and conceptual schemes or systems of representation. [It seems that concepts are things that can represent or comprehend facts. There are certain facts, Nagel thinks, that humans will never be able to form concepts or representations for, namely, the being-likes of other species.] Nagel further distinguishes facts that humans can possibly comprehend and represent and those humans cannot. So suppose all humans died before Cantor invented transfinite numbers. It was a fact that could have been represented, but never was. Likewise, humans will probably go extinct before representing every fact that humans are capable of representing. However, Nagel thinks some facts humans will never be able to represent, no matter how much time we have to work on it. What it is like to be a bat is one such fact that humans will never be able to represent in our languages and conceptual schemas. Nonetheless, we can still know that such facts exist.

This brings us to the edge of a topic that requires much more discussion than I can give it here: namely, the relation between facts on the one hand and conceptual schemes or systems of representation on the other. My realism about the subjective domain in all its forms implies a belief in the existence of facts beyond the reach of human concepts. Certainly it is possible for a human being to believe that there are facts which humans never will possess the requisite concepts to represent or comprehend. Indeed, it would be foolish to doubt this, given the finiteness of humanity’s expectations. After all, there would have been transfinite numbers even if everyone had been wiped out by the Black Death before Cantor discovered them. But one might also believe that there are facts which could not ever be represented or comprehended by human beings, even if the species lasted for ever – simply because our structure does not permit us to operate with concepts of the requisite type. This impossibility might even be observed by other beings, but it is not clear that the existence of such beings, or the possibility of their existence, is a precondition of the significance of the hypothesis that there are humanly inaccessible facts. (After all, the nature of beings with access to humanly inaccessible facts is presumably itself a humanly inaccessible fact.) Reflection on what it is like to be a bat seems to lead us, therefore, to the conclusion that there are facts that do not consist in the truth of propositions expressible in a human language. We can be compelled to recognize the existence of such facts without being able to state or comprehend them.






[Thus by means of the bat example, Nagel has accomplished his aim of showing the divergence between the subjective and objective points of view, since the subjective point of view is such that one creature may not have access to that of another creature, even while knowing that such a view does exist in the other being.]


The relevance of these observations is that they show there is a subjective character of experience. Facts regarding it “embody a particular point of view” (441/171). [The idea here might be that “point of view” is not simply one’s position of observation in the world (and thus not simply the idea that one’s own view is limited by what one is unable to perceive given one’s position), but also this view is conditioned by the biological givens that affect one’s modes of perception, activity, and so on. So the fact that we know there is something that it is like to be a bat, but also that we cannot know what that is, means that there are certain facts regarding a creature’s modes of experience that are particular to that creature, that is to say, to that creature’s subjectively oriented point of view.] Nagel will not continue with these ideas [since he already accomplished his main goal of establishing that there is this subjective character of experience.] (441/171)





[One creature can still know what it is like to be another so long as their type of experience is similar enough.]


[At this point, we might think that Nagel is saying that because there are such cases as with humans being unable to know what it is like to be a bat, that this holds in all cases. And so that would mean even two humans cannot know what it is like to be the other, since they have difference subjective points of view.] Nagel then clarifies that the differences between sorts of being-likes are matters of types, and one can know another creature’s being-like if they share a sufficiently similar type. [So bats and humans have types of experience that are too different to enable knowledge of the other’s phenomenal experiences. However, two humans, or perhaps a human and a similar species like a chimpanzee, would possibly be able to know what it is like to be the other.]

I am not adverting here to the alleged privacy of experience to its possessor. The point of view in question is not one accessible only to a single individual. Rather it is a type. It is often possible to take up a point of view other than one’s own, so the | comprehension of such facts is not limited to one’s own case. || There is a sense in which phenomenological facts are perfectly objective: one person can know or say of another what the quality of the other's experience is. They are subjective, however, in the sense that even this objective ascription of experience is possible only for someone sufficiently similar to the object of ascription to be able to adopt his point of viewto understand the ascription in the first person as well as in the third, so to speak. The more different from oneself the other experiencer is, the less success one can expect with this enterprise. In our own case we occupy the relevant point of view, but we will have as much difficulty understanding our own experience properly if we approach it from another point of view as we would if we tried to understand the experience of another species without taking up its point of view.

(441|442 / 172||173)




[What this tells us about the mind-body relation is that we cannot know what it is like to have the subjective experiences (the mental events) of a creature whose mode of experience is of a type very different from our own, on the basis of objective knowledge of their physiology (their body) regarding the way it experiences itself and the physical world.]


[Nagel’s next point seems to be the following. We can know everything about how a bat’s brain works. But we will never, on the basis of that knowledge or additionally with anything we can correlate with it, know what it is like to have the experiences corresponding to the events in the bat’s brain. Therefore, we see something about the mind-body relation, namely, that we cannot entirely explain mental events purely on the basis of objective knowledge of the body of the thing having those mental events.]

This bears directly on the mind-body problem. For if the facts of experience – facts about what it is like for the experiencing organism – are accessible only from one point of view, then it is a mystery how the true character of experiences could be revealed in the physical operation of that organism. The latter is a domain of objective facts par excellence – the kind that can be observed and understood from many points of view and by individuals with differing perceptual systems. There are no comparable imaginative obstacles to the acquisition of knowledge about bat neurophysiology by human scientists, and intelligent bats or Martians might learn more about the human brain than we ever will.






[But the inaccessibility of points of view of beings with very different types of modes of experience does not by itself disallow a reduction of subjective facts to objective ones. (For, in a sense, we can still say that the subjective facts result causally from the objective ones.) However, even if two very different species could both to a great degree understand the objective nature of something, that does not give them access to the other’s mode of experiencing that thing. (In other words, while a reduction of the subjective to the objective is possible, an expansion from the objective to the subjective is not).]


[At this point it becomes a little confusing. In the prior section, he seems to be arguing against a reductionist approach to the mind-body problem which would say that mental events can be explained purely in terms of physiological and physical phenomena that are objectively knowable. Now he says that “This is not by itself an argument against reduction”. Please consult the quote to follow, but my impression of what he is saying is the following. This is a guess, by the way. We can say that there are phenomenal features of the world, because we have them in our experience. We can take a reductionist approach which says that there is no mind involved in them but rather there is just physics and physiology. As a separate but related issue, we can also take into account the idea of subjectivity (a singular point of view) and objectivity (perhaps, the totality of all points of view, or a non-oriented point of view, or somehow a total lack of point of view of any kind). Let me further guess. The objective character of something is that aspect of it that can be experienced subjectively in many varieties of ways, depending on the physiology and mode of perceptual experience of thing perceiving it. So for example, as humans we can see the light flash of lightning, but we cannot detect its heat, at least from a distance (I am not sure that it has heat, but assume it has some quality that our physiological apparatus cannot perceive directly or at least at a distance). However, some other being could conceivable perceive other features of the lightning that we cannot perceive. Furthermore, we might say that the thing in its objectivity might have more features than can be perceived by any living creature. On the other hand, the subjective character of something is that particular way it is experienced by some creature with its own characteristic mode of perception. With all this being understandable, the question then is, how do these ideas suggest that reductionism is still feasible under Nagel’s considerations so far? Perhaps his point is the following. The reduction of phenomenal features to physical features is still perhaps possible, because the phenomenal features result from the physical circumstances of the perceived thing in its relation to the physiology of the perceiving thing. So if we know everything about the physiology of the creature and everything about the physical features of the thing, along with how perception would work in their interaction, then we can perhaps know what sorts of phenomenal features are being perceived in that event. For example, if the thing being perceived is the walls of a cave, and the thing perceiving it a bat, then we can know that the spatial sorts of features of the cave are being perceived by means of echolocation by the bat. (Also note that the objective features of the cave remain the same when simultaneously a human looks at it.  So this perhaps lends to the idea that the objective features are more substantial than the phenomenal features, because the phenomenal ones can vary while the objective ones do not.) Thus, so long as we take into consideration the physical substrate of the experiential situation, we think reductively about the relation between phenomenal features and physical features. But, as we will perhaps infer from the next paragraph, we should not confuse this reduction with a reduction of the subjective to the objective. Just because we can reductively understand what sort of experience the bat is having does not mean that we know what it is like to have the bat’s experience from its own point of view. In other words, and I am guessing, Nagel is distinguishing two sorts of reduction, with the phenomenal-to-physical being possible, but the subjective-to-objective not. Please consult the quotation to be sure.]

This is not by itself an argument against reduction. A Martian || scientist with no understanding of visual perception could understand the rainbow, or lightning, or clouds as physical phenomena, though he would never be able to understand the human concepts of rainbow, lightning, or cloud, or the place these things occupy in our phenomenal world. The objective nature of the things picked out by these concepts could be apprehended by him because, although the concepts themselves are connected with a particular point of view and a particular visual phenomenology, the things apprehended from that point of view are not: they are observable from the point of view but external to it; hence they can be comprehended from other points of view also, either by the same organisms or by others. Lightning has an objective character that is not exhausted by its visual appearance, and this can be investigated by a Martian without vision. To be precise, it has a more objective character than is revealed in its visual appearance. In speaking of the move from subjective to objective characterization, I wish to remain noncommittal about the existence of an end point, the completely objective intrinsic nature of the thing, which one might or might not be able to reach. It may be more accurate to think of objectivity as a direction in which the understanding can travel. And in understanding a phenomenon like lightning, it is legitimate to go as far away as one can from a strictly human viewpoint.

(443 / 172||173)





[So something objectively can be perceived differently by different creatures from their own points of view. But each subjective experience would seem to not have an objective character, as what is most essential to it is the particular point of view, which is the opposite of objective. Nevertheless, we still want to say that it is on account of the objective character of the physiology involved in one’s own subjective experiences that allow other sorts of creatures to see from their point of view that we ourselves are having a subjective experience.]


[Building from the above bracketed commentary, which was composed of some guesswork, we might summarize the next paragraph in the following way. If we just look at the thing being perceived, like the lighting, we can say that the objective character is that about it which can cause different sorts of experiences for different sorts of physiologies. If we just look at the experience itself, we would have trouble saying what its objective character is. I am not certain, but Nagel might be defining objective character as something like that which were you to subtract it you would lose the thing itself. For, he writes: “It is difficult to understand what could be meant by the objective character of an experience, apart from the particular point of view from which its subject apprehends it. After all, what would be left of what it was like to be a bat if one removed the viewpoint of the bat?” But I thought by objective he meant something like the opposite of having a particular point of view. So I am a little confused by what he is saying here. At any rate, his point will be that on the one hand it would seem that experience does not have an objective nature, as it has a point of view. However, on the other hand, we also seem to be assuming that one’s own subjective experiences, especially with regard to the physiology involved in that experience, can be observed by other creatures from their own point of view. Maybe here Nagel is saying for example that we might do an MRI scan of a bat while it is perceiving space, and we might say that we are seeing its experience from our own point of view. Thus furthermore we would want to say that experience does have an objective side to it. Let me quote, as I may very well by misunderstanding.]

In the case of experience, on the other hand, the connexion with a particular point of view seems much closer. It is difficult to understand what could be meant by the objective character of an experience, apart from the particular point of view from which its subject apprehends it. After all, what would be left of what it was like to be a bat if one removed the viewpoint of the bat? But if experience does not have, in addition to its subjective character, an objective nature that can be apprehended from | many different points of view, then how can it be supposed that a Martian investigating my brain might be observing physical || processes which were my mental processes (as he might observe physical processes which were bolts of lightning), only from a different point of view? How, for that matter, could a human physiologist observe them from another point of view?

(443|444 / 173||174).





[In non-phenomenological investigations where our object of study is not the subjective point of view, it is less problematic to incorporate a psychophysical reduction. Granted, in these other cases, we begin with our own perceptual/sense data from our limited subjective point of view. However, it is directed toward something objective, and we can make a psychophysical reduction to the objective effects and properties of the examined thing. ]


Nagel notes that in other areas of psychophysical reduction, it is a move toward greater objectivity, which means a move toward “a more accurate view of the real nature of things”. He says this is done by reducing individual or species-specific points of view to the object we are investigating (174/444). He then clarifies that we begin with our own sense-based experience of the object of investigation and move toward a descriptions of its “more general effects and of properties detectable by means other than the human senses” (174/444). We can do this because although we begin with our subjective point of view and its perceptual data, we are directed toward something outside us (174/444).

We appear to be faced with a general difficulty about psychophysical reduction. In other areas the process of reduction is a move in the direction of greater objectivity, toward a more accurate view of the real nature of things. This is accomplished by reducing our dependence on individual or species-specific points of view toward the object of investigation. We describe it not in terms of the impressions it makes on our senses, but in terms of its more general effects and of properties detectable by means other than the human senses. The less it depends on a specifically human viewpoint, the more objective is our description. It is possible to follow this path because although the concepts and ideas we employ in thinking about the external world are initially applied from .a point of view that involves our perceptual apparatus, they are used by us to refer to things beyond themselves – toward which we have the phenomenal point of view. Therefore we can abandon it in favor of another, and still be thinking about the same things.






[We cannot study experience by reducing it to the objective, because it is only accessible from a particular subjective point of view.]


But this manner of moving toward greater objectivity does not work for the study of experience, which is only accessible from one particular subjective point of view.

Experience itself, however, does not seem to fit the pattern. The idea of moving from appearance to reality seems to make no sense here. What is the analogue in this case to pursuing a more objective understanding of the same phenomena by abandoning the initial subjective viewpoint toward them in favour of another that is more objective but concerns the same thing? Certainly it appears unlikely that we will get closer to the real nature of human experience by leaving behind the particularity of our human point of view and striving for a description in terms accessible to beings that could not imagine what it was like to be us. If the subjective character of experience is fully comprehensible only from one || point of view, then any shift to greater objectivity – that is, less attachment to a specific viewpoint – does not take us nearer to the real nature of the phenomenon: it takes us farther away from it.

(444||445 / 174)





[If our scientific investigation reduces a phenomenon like sound to the physical wave events in the surrounding media, we have left unreduced still the subjective auditory experience of the sound that we began with in our investigation. So we see already the seeds of this objection even in the “successful” cases of reduction to objectivity. Furthermore, even when different species obtain this objective knowledge, they can only do so by leaving aside an understanding of the other’s species’ ways of experiencing the thing and focusing instead on the “common reality” shared by both.]


[Nagel’s next point might be the following. We said two paragraphs before that in certain sorts of scientific investigations, the psychical elements of the investigation, like the perceptual data coming from the investigator’s subjective point of view, are reduced to more objective features and effects of the thing studied. Nagel now gives the example of sound to be no more than a wave phenomenon in the air or other media around us. But his point here is that there is still an element that we began with that is still not yet reduced, namely, the auditory phenomenon of the creature hearing the sound. Thus, as he says at the beginning of this paragraph, “the seeds of this objection to the reducibility of experience are already detectable in successful cases of reduction”. Nagel’s following point is a bit trickier. He first points out that two species can both form an objective understanding of the same physical events that they each experience in their own ways. Furthermore, this objective understanding involves not necessarily that they know what it is like for the other species to experience that thing but rather that they can refer to some “common reality” (which might be the objective features of the thing. In our example of the cave walls, both humans and bats might discern the wall’s topological variations, even though each species is unable to know how the other experiences those features by means of their unique perceptual modality.)]

In a sense, the seeds of this objection to the reducibility of experience are already detectable in successful cases of reduction; for in discovering sound to be, in reality, a wave phenomenon in air or other media, we leave behind one viewpoint to take up another, and the auditory, human or animal viewpoint that we leave behind remains unreduced. Members of radically different species may both understand the same physical events in objective terms, and this does not require that they understand the phenomenal forms in which those events appear to the senses of members of the other species. Thus it is a condition of their referring to a common reality that their more particular viewpoints are not part of the common reality that they both apprehend. The reduction can succeed only if the species-specific viewpoint is omitted from what is to be reduced.

(445 / 175)





[So we cannot turn toward an objectifying reductionist method to explain experience, which has an intrinsic and essential element of a subjective point of view.]


[So we have said that when our concern is simply the objective features of something outside our inner experience and commonly available to the knowledge of many types of creatures, it is perhaps ok to use the subjective point of view we creatures take on it when studying it. He emphasizes now that this does not work when studying experience. For, this subjective point of view is not something extraneous or superficial to, or unimportant with respect to, the experience itself. Rather, it is essential to it, and therefore it cannot be reduced or ignored when studying it. Thus neobehaviorism, which tries to explain the mind merely on the basis of objective data, simply substitutes “an objective concept of mind for the real thing”. And no physical theory of the mind can account the subjective character of experience (because they can only tell us about the objective character).]

But while we are right to leave this point of view aside in seeking a fuller understanding of the external world, we cannot ignore it permanently, since it is the essence of the internal world, and not merely a point of view on it. Most of the neobehaviorism of recent philosophical psychology results from the effort to substitute an objective concept of mind for the real thing, in order to have nothing left over which cannot be reduced. If we acknowledge that a physical theory of mind must account for the subjective character of experience, we must admit that no presently available conception gives us a clue how this could be done. The problem is unique. If mental processes are indeed physical processes, then there is something it is like, intrinsically, to | undergo certain physical processes. What it is for such a thing to be the case remains a mystery.

(445|446 / 175)





[One conclusion we can draw from these findings is that physicalism is not necessarily false, because it is still coherent and could be shown to be true, were the right physical processes somehow discovered.]


Nagel will now tell us what we can conclude from all this and how we might move forward in our studies of experience. His first conclusions is that we should not regard physicalism as being false. [I do not follow his reasoning here, so please consult the quotation to follow. Nagel might be saying that physicalism could still be true, if we knew exactly which physical processes and states are those which are mental. And right now we still do not know what they are, but we might someday know this. I am guessing, but the basic insight here might be that there could still be an objectively observable physiological process whose features somehow give us access to the being-like of that creature. Let me quote so you can see:]

What moral should be drawn from these reflections, and what should be done next? It would be a mistake to conclude that physicalism must be false. Nothing is proved by the inadequacy of physicalist hypotheses that assume a faulty objective analysis of mind. It would be truer to say that physicalism is a position we cannot understand because we do not at present have any conception of how it might be true. Perhaps it will be thought unreasonable to require such a conception as a condition of understanding. After all, it might be said, the meaning of physicalism is clear enough: mental states are states of the body; mental events are physical events. We do not know which physical states and events they are, but that should not prevent us from | understanding the hypothesis. What could be clearer than the words ‘is’ and ‘are’?

(446|447 / 176)






[The physicalist equation of “mental events are physical events” takes the form of X is Y. But while we now what the X and the Y refer to, they are both such very different things that we also do not know what sorts of things might be both X and Y. So what is lacking in the physicalist account is the theoretical framework that can allow us to know how these terms might converge upon the same referenced thing.]


[So the physicalist view says that mental states are states of the body; mental events are physical events. We here have an identification of an X and a Y (X is Y) that could in theory hold, were instances of that identification to be discovered. Nagel now says that the ‘is’ of this identification (X is Y) does not tell us how these two terms might be found to converge upon a singular thing. So we know what ‘mental states’ and ‘mental events’ refers to, and we know what ‘states of the body’ and ‘physical events’ refers to. But we do not seem to have a sufficient conception of how these two sets of referential terms might converge upon a singular reference. What is still needed is a theoretical framework that can explain how this convergence could be understood.]

But I believe it is precisely this apparent clarity of the word ‘is’ that is deceptive. Usually, when we are told that X is Y we know how it is supposed to be true, but that depends on a conceptual or theoretical background and is not conveyed by the ‘is’ alone. We know how both ‘X’ and ‘Y’ refer, and the kinds of || things to which they refer, and we have a rough idea how the two referential paths might converge on a single thing, be it an object, a person, a process, an event or whatever. But when the two terms of the identification are very disparate it may not be so clear how it could be true. We may not have even a rough idea of how the two referential paths could converge, or what kind of things they might converge on, and a theoretical framework may have to be supplied to enable us to understand this. Without the framework, an air of mysticism surrounds the identification.

(447 / 176||177)





[In fact anytime science discovers an X is Y equation between disparate sorts of things, it takes on a magical or mystical character when explained without the necessary theoretical background, as in cases of popular presentations of such scientific discoveries (like ‘all matter is energy’).]


So when the theoretical framework for how to make an X is Y equation where the X and Y are very different things, the notion of the equation can seem somewhat mystical. This explains why when popular presentations of such scientific discoveries where they are presented without that complicated framework (like when teaching young people that all matter is really energy), the notions have a certain “magical flavor” (447/177).





[Thus physicalist and behaviorist accounts that reduce mental events to physical ones fail, because they are so far unable to explain how these terms can refer to the same entity.]


Thus the physicalist equation of ‘a mental event is a physical event’ is currently inadequate, because we still lack an understanding of how the two terms can refer to the same entity. [Nagel then explains why current attempts fail at this. I do not understand them, so please consult the quotation to follow. He writes: “They fail because if we construe the reference of mental terms to physical events on the usual model, we either get a reappearance of separate subjective events as the effects through which mental reference to physical events is secured, or else we get a false account of how mental terms refer (for example, a causal behaviorist one).” I will try to break them down as best I can. There are two attempts to use analogies with theoretical identification, and they fail to explain how the equation of mind and body works. In the first case, we have physical events. (Let us suppose an example being some neurological activity happening when one sees something). And we have mental reference to those events. (Maybe an example of this would be the subjective experience of seeing that thing, the being-like of it.) There is then something which secures this mental reference to the physical events. What is doing that securing in the first case is ‘a reappearance of separate subjective events’. (I have no idea what this means. Perhaps this first case of the “usual model” is like the example of explaining sound as waves while losing the auditory element. But here I do not know what the separate subjective events are. So this is as far as I can understand this first one. Perhaps the idea is that you have as one subjective event the creature having the experience, and the second subjective event is the observer attempting to replicate that first creature’s subjective experience but failing to do so. I am just guessing blindly.) The second instance has as an example the causal behaviorist account. It is said to give a false account of how mental terms refer. (I am not at all sure, but perhaps the idea here is that the behaviorist account puts aside any subjective element, and thus there is no basis for saying that the objective facts correspond some subjective ones.) Let me quote so you can see for yourself what is meant:]


At the present time the status of physicalism is similar to that which the hypothesis that matter is energy would have had if uttered by a pre-Socratic philosopher. We do not have the beginnings of a conception of how it might be true. In order to understand the hypothesis that a mental event is a physical event, we require more than an understanding of the word ‘is’. The idea of how a mental and a physical term might refer to the same thing is lacking, and the usual analogies with theoretical identification in other fields fail to supply it. They fail because if we construe the reference of mental terms to physical events on the usual model, we either get a reappearance of separate subjective events as the effects through which mental reference to physical events is secured, or else we get a false account of how mental terms refer (for example, a causal behaviorist one).







[But possibly we can know that the physicalist position holds even without knowing how it does. Analogously, suppose we do not know how insect metamorphosis works, but we see a caterpillar now and later see it became a butterfly, then we know that the two are somehow one and the same creature, even if we do not know in what sense this is so.]


[So one problem we are saying with physicalism is that it asserts that there is something we can know, namely, that mental events are physical, but it does not give us a way to understand how that identification can be so. However, we can still have reason to think that things we do not know how to be so still can be known that they are so. Nagel gives the example of a person who does not know about insect metamorphosis. They put a caterpillar in a safe and open it some weeks later to find a butterfly. The person can know that the butterfly is or was once the caterpillar without knowing in what sense this is so. Thus, Nagel seems to be implying, we can know with certainty that the physicalist position is true, but we may not know in what sense mental events are physical.]

Strangely enough, we may have evidence for the truth of some-|thing we cannot really understand. Suppose a caterpillar is locked in a sterile safe by someone unfamiliar with insect metamorphosis, and weeks later the safe is reopened, revealing a butterfly. If the person knows that the safe has been shut the whole time, he has reason to believe that the butterfly is or was once the caterpillar, without having any idea in what sense this might be so. (One possibility is that the caterpillar contained a tiny winged parasite that devoured it and grew into the butterfly.)

(447|448 / 177)






[Davidson’s physicalism for example claims that certain physical events have mental properties even though it may be impossible to ever know how that is so. This nonetheless is still problematic, because we still do not know how to form a conception of the situation, which is what a theory of experience needs.]


Donald Davidson makes such a defense of physicalism by arguing that so far as mental events can be said to have physical causes and effects, they also must have physical descriptions. And Davidson says we should believe this even if it would be impossible to have a general psychophysical theory. [Nagel does not say more, but he cites articles by Davidson and himself. Not having read them yet, I cannot summarize the reasoning behind this argument.] Nagel says that although Davidson’s argument applies only to intentional mental events, it can also apply to sensations as well. [The next part I have trouble with again because I am not familiar with the sources, but it seems first to state that Davidson argues that certain physical events have mental properties that cannot be reduced to those physical ones. Nagel then acknowledges that this view could be correct. However, he adds that we do not have any sort of notion or theory that could allow us to form a conception of how that is so.]

It is conceivable that we are in such a position with regard to physicalism. Donald Davidson has argued that if mental events have physical causes and effects, they must have physical descriptions. He holds that we have reason to believe this even though we do not – and in fact could not – have a general psychophysical theory.12 His argument applies to intentional mental events, but I think we also have some reason to believe that sensations are physical processes, without being in a position to understand how. Davidson’s position is that certain physical events have irreducibly mental properties, and perhaps some view describable in this way is correct. But nothing of which we can now form a conception corresponds to it; nor have we any idea what a theory would be like that enabled us to conceive of it.13


[Footnotes 12 and 13, on pages 448/178 (with bibliographic formatting different in each Nagel text, this one from the 1979 edition):

12 See ‘Mental Events’ in Experience and Theory, ed. Lawrence Foster and J. W. Swanson (Amherst: University of Massachusetts Press, 1970); though I do not understand the argument against psychophysical laws.

13 Similar remarks apply to my paper ‘Physicalism’, Philosophical Review, LXXIV (1965), 339-56, reprinted with postscript in Modern Materialism, ed. John O’Connor (New York: Harcourt Brace Jovanovich, 1969).






[Since we do not know in what sense subjective experience can have objective character, we cannot fully make sense of available physicalist theories, which purport to make that reduction.]


[I may not be following the next idea. Nagel seems to be making the following point. The reductive approach would want to distinguish between the way experiences appear to us (from our subjective point of view) from the way they are in ‘reality’ (objectively speaking). But we do not yet know how it could be that an experience can be said to have some sort of objective character.]

Very little work has been done on the basic question (from which mention of the brain can be entirely omitted) whether any sense can be made of experiences’ having an objective character at all. Does it make sense, in other words, to ask what my experiences are really like, as opposed to how they appear to me? We cannot genuinely understand the hypothesis that their nature is captured in a physical description unless we understand the more fundamental idea that they have an objective nature (or that objective processes can have a subjective nature).






[One solution to the problem of not knowing other species’ being-likes is to formulate an “objective phenomenology” that does not depend on the abilities of one creature to imagine or empathize with other creatures.]


[Now Nagel will propose what we might do about these problems. He notes that the problem with giving an objective account of experience is that experience is essentially something subjective and not objective. He further reminds us that the problem with the subjectivity involved is that certain species would be unable to know the subjective features of the mental lives of other species. This he also reminds us was a result of the limits of the imagination to come to such an empathic understanding. What he proposes is the creation of an “objective phenomenology” that does not depend on the empathy or imagination but that somehow instead constructs descriptions of experience that are comprehensible to other beings that are unable to have these experiences.]

I should like to close with a speculative proposal. It may be possible to approach the gap between subjective and objective from another direction. Setting aside temporarily the relation between the mind and the brain, we can pursue a more objective understanding of the mental in its own right. At present we are completely unequipped to think about the subjective character of experience without relying on the imagination – without taking up the point of view of the experiential subject. This | should be regarded as a challenge to form new concepts and devise a new method – an objective phenomenology not dependent on empathy or the imagination. Though presumably it would not capture everything, its goal would be to describe, at least in part, the subjective character of experiences in a form comprehensible to beings incapable of having those experiences. We would have to develop such a phenomenology.

(449 / 178||179)





[An objective phenomenology would allow one species to know what it is like to have the experience of very different species, and it would also allow one human to know what it is like to have the experiences of another human with different physiological circumstances, like a blind person learning from an adequate objective description what it is like to see something. What would not work in such a case are intermodal analogies like “Red is like the sound of a trumpet”, because they do not communicate effectively the subjective features of the experience. Rather, it would be some sort of description that somehow conveys the structural features of the perception.]


Nagel then further explains what such an objective phenomenology would be like. It for example would allow us to describe what it is like to have the sonar experiences that bats have. It would also allow us to describe certain sorts of experiences that other humans have that we cannot have. For example, we might find a way to describe to a blind person what it is like to see something. Nagel claims that what will not work are  intermodal analogies, like the classic ‘Red is like the sound of a trumpet’ [see for example C.S. Peirce’s discussion of it in CP1.312, CP1.313, CP1.314]. [Nagel does not explain why. He simply says it is obvious for anyone who has seen red and heard a trumpet. But I am not sure how we can know that there are not analogies which would be effective, as perhaps a gifted poet might be more able to supply one.] However, we might have more success providing an objective description for the “structural features of perception”, even though we probably would have to leave out certain uncommunicable features of the experience. [I am not sure what exactly would be a structural feature of perception in this case. Perhaps it could be something to do for example with the ways parts of the experience are distributed over time, or other sorts of structural relations between parts of the experience like order, predominance, simultaneity, or I do not know what.] [I am not sure I follow Nagel’s next point. He refers to concepts that we learn in the first person. He then says that alternate concepts to those could help us understand our own experience in perhaps a more objective way. Without examples or further elaboration, I am not sure what he is referring to. Please consult the quotation:]

We would have to develop such a phenomenology to describe the sonar experiences of bats; but it would also be possible to begin with humans. One might try, for example, to develop concepts that could be used to explain to a person blind from birth what it was like to see. One would reach a blank wall eventually, but it should be possible to devise a method of expressing in objective terms much more than we can at present, and with much greater precision. The loose intermodal analogies – for example, “Red is like the sound of a trumpet” – which crop up in discussions of this subject are of little use. That should be clear to anyone who has both heard a trumpet and seen red. But structural features of perception might be more accessible to objective description, even though something would be left out. And concepts alternative to those we learn in the first person may enable us to arrive at a kind of understanding even of our own experience which is denied us by the very ease of description and lack of distance that subjective concepts afford.






[We need such an objective phenomenology in order to deal better with questions regarding the physical basis of experience. And we need to deal with the problem of subjectivity and objectivity with regard to experience in order to better grapple with the mind-body problem.]


[Nagel’s final points seem to be the following. {1} if we have such an objective phenomenology, then we can more intelligibly account for the physical basis of mental phenomena. (I am not sure why, however. From what was said above, there was no indication that the physical component would enter the description, although the “objective features” of the experience would be, and perhaps they are to be understood as physical. See the footnote for this first point, as it might further explain this objective-physical relation.) {2} “Aspects of subjective experience that admitted this kind of objective description might be better candidates for objective explanations of a more familiar sort”. (I quote because I do not know what he means by “objective explanations of a more familiar sort”, but the rest of the point seems clear to me.) {3} Before we can further work with physicalist theories, we need first to better understand the problem of the subjective and objective with respect to the study of experience. If we do not do this, then we cannot really deal with the mind-body problem.]

Apart from its own interest, a phenomenology that is in this sense objective may permit questions about the physical15 basis of experience to assume a more intelligible form. Aspects of subjective experience that admitted this kind of objective description might be better candidates for objective explanations of a more familiar sort. But whether or not this guess is correct, || it seems unlikely that any physical theory of mind can be contemplated until more thought has been given to the general problem of subjective and objective. Otherwise we cannot even pose the mind-body problem without sidestepping it.

(449|450 / 179||180)

[Footnote 15 from page 449|450 / 179 (following the 1974 edition):

15 I have not defined the term “physical.” Obviously it does not apply just to what can be described by the concepts of contemporary physics, since we expect further developments. Some may think there is nothing to prevent mental phenomena from eventually being recognized as physical in their own right. But whatever else may be said of the physical, it has to be objective. So | if our idea of the physical ever expands to include mental phenomena, it will have to assign them an objective character – whether or not this is done by analyzing them in terms of other phenomena already regarded as physical. It seems to me more likely, however, that mental-physical relations will eventually be expressed in a theory whose fundamental terms cannot be placed clearly in either category.










Nagel, Thomas. (1974). “What Is It Like to Be a Bat?” The Philosophical Review, Vol. 83, No. 4 (Oct., 1974), pp. 435-450.


Nagel, Thomas. (1979). “What Is It Like to Be a Bat?” In Mortal Questions, pp.165-180 (chapter 12). Cambridge: Cambridge University.




1 Nov 2016

Thomas Nagel, entry directory


by Corry Shores


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[Phenomenology, entry directory]




Entry Directory for


Thomas Nagel



(image from Modern Psychologist)



“What Is It Like To Be a Bat?”


Nagel’s “What Is It Like To Be a Bat?”, summary





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Phenomenology, entry directory


by Corry Shores


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Entry Directory for

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Dainton. Barry Dainton


Barry Dainton, entry directory



Husserl. Edmund Husserl


Edmund Husserl, entry directory



Nagel. Thomas Nagel


Thomas Nagel, entry directory



Merleau-Ponty. Maurice Merleau-Ponty


Merleau-Ponty, entry directory