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Thinking fish & zombie caterpillars

3:AM: You argue, I think, that if representationalism is right then questions such as whether fish have qualia, or plankton, can be answered. Is that right? So do fish and plankton? And are there creatures that are zombies?

MT: Fish have experiences. Plankton don’t. Honeybees have experiences. Caterpillars don’t. Caterpillars are zombies. Fish have eyes and ears (though not external ears but hidden ear-like structures) and a sense of smell, and the behaviour they engage in on the basis of the information they glean from these senses shows considerable flexibility. Fish learn to recognise markings and patterns, to avoid artificially colored, unpleasant-tasting fish they would normally eat, to solve problems in order to reach feeding places. Fish can find their way through mazes and they defer to other fish that are better at finding their way through when they are in groups. Cumulatively the evidence seems best explained by supposing that fish often make cognitive classifications or assessments, directly in response to the information conveyed to them by their senses, and that these, together with their goals, often determine their behavior.

There may be some reluctance to say that fish have beliefs. Clearly, a fish cannot believe that a hand is dangling in the water. Fish lack the concept hand. And, in general, it seems unlikely that fish share many concepts with us. But the fact that there are striking conceptual differences, that our concepts are much richer and more articulated than theirs, does not show that they lack any concepts at all. Possessing a perceptual concept, in my view, is (roughly) a matter of having a stored memory representation that has been acquired through the use of sense-organs and that is available for retrieval, thereby enabling a range of discriminations to take place. Perceptual beliefs are (roughly) representational states that bring to bear such concepts upon stimuli and that interact in rational ways, however simple, with one another and other representational states the creature generates in response to its needs, thereby determining behavior. In this sense, given the facts adumbrated earlier about fish behavior, it seems to me very plausible to suppose that fish form simple beliefs on the basis of immediate, sensory representations of their environments. These sensory representations, given where they arise in the information processing and the downstream role they play in the production of beliefs, just are experiences.

What is true for fish is true for honeybees. Honeybees have sense organs. For example they have eyes and ‘ears’ and a sense of smell. And they engage in intelligent or apparently intelligent behavior. Take the case of children who are starting to learn the alphabet. They can discriminate different letters, whatever their size or font. Pigeons can be trained to do this also. So too can honeybees up to a point. Some bees can recognise the letter B in different orientations, colors, sizes, and fonts. Apparently, then, they can form novel concepts of items not normally found in their natural habitats.

Here is a striking example of apparently intelligent behaviour in honeybees. The flowers of alfalfa possess anthers that spring forward and deliver a heavy blow in response to pressure. Once honeybees have been hit by the alfalfa anther, they avoid alfalfa like the plague. But if they are taken to a region of many acres of alfalfa and set free there, they are compelled to confront the problem or starve to death. So, they do one of two things: either they learn to identify flowers, the anthers of which have already sprung, and they only alight on the sprung ones or they learn to get at the nectar by chewing through the flower from the side without ever setting off the anther. For the same reasons as fish, then, honeybees have experiences. They are not zombies.

What about caterpillars? Is there anything it is like to be a caterpillar? Different kinds of caterpillars show different sorts of behavior upon hatching. Some, for example, eat the shells of the eggs from which they emerge; others crawl away from their cells immediately. But there is no clear reason to suppose that caterpillars are anything more than stimulus-response devices. They have a very limited range of behaviours available to them each of which is automatically triggered at the appropriate time by the appropriate stimulus. Consider, for example, their sensitivity to light. Caterpillars have two eyes, one on each side of the head. Given equal light on both eyes, they move straight ahead. But given more light on one of the eyes, that side of the body locomotes more slowly. So, when caterpillars move, they tend to move towards the direction of most intense light. This is why caterpillars climb trees all the way to the top. The light there is strongest. Shift the light to the bottom of the tree, and the caterpillar will go down, not up, as it usually does, even if it means starving to death. Remove one of its eyes, and it will travel in a circle without ever changing its route.

Once one is made aware of these facts, there seems no more reason intuitively to attribute phenomenal consciousness to a caterpillar on the basis of how it moves than to an automatic door. The latter responds in a fixed, mechanical way to the presence of pressure on a plate in the floor or ground in front of it, just as the former responds mechanically to the presence of light. There is no learning, no variation in behavior with changed circumstances, no reasoned assessment.

Again, this is the result my theory delivers. Caterpillars do not move purposefully. They do not believe that the light is strongest at the tops of trees. They do not want to get to the strongest light. There is nothing in any of their behavior that seems to require the admission that they have any wants or beliefs. So, caterpillars do not support sensory representations on the basis of which beliefs and desires are formed. None of their representations are appropriately cognitively poised. Caterpillars, then, are not phenomenally conscious any more than are plants. And what goes for caterpillars and plants goes for plankton.

[Dave Chalmers, left, with Michael Tye]

3:AM: Talking of which, does your view preclude a view of Chalmers zombie world – exactly like ours but without consciousness?

MT: Chalmers zombie world is conceptually possible. No amount of a priori reflection alone will show that there can be no such world. Even so, zombie world is metaphysically impossible. That is all that my theory of phenomenal consciousness requires.

Consider the claim that water is H2O. That was a scientific, a posteriori discovery. Water has a certain hidden nature that science has revealed. Is it conceivable that water isn’t H2O? Certainly. It is conceivable, though incredibly unlikely, that scientists have made a mistake about the nature of water. It is even conceivable that the atomic theory of matter is mistaken. But if in fact science has gotten things right and in fact water is H2O, then there is no possible world in which water is not H2O.

I think of my theory about phenomenal consciousness as being somewhat like this. The theory is justified in terms of its overall explanatory power. No claim is made that it is incoherent to deny the theory, that it is inconceivable that the theory is mistaken. Still, if it is true, it is necessarily true – and Chalmer’s zombie world is then metaphysically impossible though it cannot be ruled out a priori.

3:AM: A big debate with lots of legs is the one about whether colours adhere out there in the world or are the subjective products of our minds. How does your theory handle this question? Are roses really red? And how is it analogous to feeling pain? Ned Block thinks pain is harder to explain on your theory than colour (and that your theory fails) but thinks you are heroic in your efforts. Why is Block wrong?

MT: Yes, roses really are red. That’s a piece of commonsense. It’s also what our experience tells us. We experience colours as covering the surfaces of objects (as with roses) or sometimes filling volumes of liquid (as with wine) or less commonly inhering in films. Unless our colour experiences are radically mistaken, colours must be out there in the world in the sense of being properties of external things. This leaves open, of course, whether colours have a fully objective hidden nature, whether they are simple qualities, or whether they are subject-dependent properties. The last alternative is compatible with colours being properties of objects. It holds that the relevant properties are dispositions the objects have to produce certain subjective responses in perceivers. On this view, red is the disposition an object has to cause a normal perceiver of the object located in standard viewing conditions to have a certain colour experience. And here lies the rub: which colour experience? Obvious answer: the experience of red. But now the proposal is circular. It tells us what red is in part by reference to red.

The circularity can be avoided by saying that the relevant subjective experience is a red* experience, where ‘red*’ denotes an intrinsic, introspectible, subjective property of the experience. Red now is the disposition to produce in normal perceivers in standard conditions red* experiences. The trouble is that there is no such property.

We are driven, then, either to the view that colours have a hidden scientific nature or that they are simple. I opt for the former alternative and I think of colours as reflectances.

Just as colour experiences are perceptual experiences of a certain sort, namely those that represent reflectance patterns, so pain experiences, in my view, are quasi-perceptual experiences that represent certain bodily disturbances. The relevant disturbances involve actual (or potential) tissue damage of one sort or another. The full story here is complicated and I pass over the complications except to note that there is, in my view, an evaluative component to pain experience. Pains feel bad. This is accommodated, on my account, by holding that pain experiences represent the relevant bodily disturbances as being bad for one (as being apt to harm). The flip side of the coin is that of orgasms. They feel good, very good (which is why sex is so popular); and this is because they are experiences that represent different bodily changes as being good for one (as apt to benefit).

Pain experiences are quasi-perceptual in that admit of cases of hallucination and illusion. A pain in a phantom limb is an experience that represents tissue damage in a limb that no longer exists. This is a case of hallucination. A pain in the left arm when the disturbance triggering the pain is in the heart is an experience that erroneously represents the disturbance as being in the arm. This is a case of illusion.

What makes the pain case more complicated than that for colour is that for color we allow that there is an appearance/reality distinction. Something can look red without really being red and something can be red without looking red. This is not true in the case of pain. If something seems/feels painful to you, it is painful. And if it is painful, it seems/feels painful. The explanation is straightforward. Pain is an experience or feeling. Colour is not. This is why there can be no pains in a world without sentient creatures but there can be colors in such a world. If all sentient creatures on earth ceased to exist there would still be red and blue and yellow objects.

3:AM: One of the things that happens in your explanations is that ‘awareness of’ turns into ‘awareness that’. Is this like Jason Stanley’s arguments that ‘knowing how’ is always a case of ‘knowing that’? And like when Fodor disputes Wittgenstein and all meaning holists and connectionists who says you shouldn’t explain meaning in terms of use and how terms function in the whole language web but in terms of propositions? Is inverting the common order of explanation often a good way of beginning to get hold of an idea?

MT: My thesis about awareness is not really like the other theses you cite. Philosophers distinguish between de re awareness – awareness directed on particular things or properties – and de dicto awareness – awareness that so-and-so is the case. I accept this distinction. I am also prepared to accept that in ordinary life we may say such things as the following: when I turn my attention inwards, I am aware of my experience of a tomato, say. But often when we speak this way and use the term ‘of’ in connection with experiences, we really have in mind de dicto awareness, not de re awareness. Consider, for example, my saying of you that I am aware of your penchant for driving fast. This might be understood in a de re way; but a more natural reading is that I am aware that you have a penchant for driving fast.

Earlier, when I said that we are introspectively aware of our experiences, I meant that we do not have de re awareness of them. They are not objects of our awareness. We are certainly aware (de dicto) that we have experiences of cars and trees and people and colours and so on.

3:AM: The economist uses psychology of change blindness in explaining why economists missed the information that would have warned them that the crash was coming. You discuss attention, seeing and change blindness because it helps us think about the character of our visual experiences, helps us think about the role of attention, and about the vehicles of awareness. Can you say how you think we should think about each of these things, and can you say whether this only extends to visual experiences or do we learn things about experience and thought generally?

MT: This is an enormously broad question, so I can only skate the surface here. A natural view to take of consciously seeing a thing is that it is a matter of undergoing a visual experience (using the eyes) that makes one conscious of that thing. But what is it to be conscious of a thing? Evidently, I can be conscious of a thing without being able to identify the thing. Think, for example, of being conscious of a thing located on the other side of thick, distorting, darkened glass. I might be able to see the thing and track its movements without having the faintest idea what it is.

Still even if I can’t identify a thing, if I am conscious of it then it must be marked out or differentiated in the phenomenology of my experience. For suppose that it is not. Then I won’t even be able to mentally point to the thing on the basis of my experience. So, my experience alone does not enable me even so much as to wonder “What is that?” with respect to the thing. Nor does my experience alone enable me directly to form beliefs or make judgments about the thing. The thing thus is hidden from me. I am blind to it. I am not conscious of the relevant thing.

So when am I conscious of a thing? The above remarks suggest the following test: I am conscious of a thing just in case my experience has a phenomenal character directly on the basis of which I can at least ask myself “What’s that?” with respect to the thing (or form some singular belief about it).

Here is another way to motivate the above test. Consider a perfectly camouflaged moth on a tree trunk. The moth is in plain view. Do I see it? What about the blob of white-out on the page of white paper? I have no idea where it is on the paper, as I hold the page before me. Do I see it?

As for the case of simple creatures without the capacity to form propositional attitudes, for example, caterpillars. I deny that they see things around them (in the relevant sense of ‘see’). I do not deny, of course, that such creatures may register or detect things in their environments and thus see them in a weaker sense.

It seems to me that the natural, intuitive view to take is that I am not conscious of either the perfectly camouflaged moth or the blob of white-out. But why not? In the moth case, surely I am not conscious of the moth because my visual experience is not about the moth at all.

It might be replied that this is mere prejudice. My experience is about the moth. But then how does my experience latch onto the moth? After all, the moth is not marked out or differentiated in the phenomenology of my experience. I cannot mentally point to it. So, I can’t even ask myself “What’s that?’ with respect to the moth directly on the basis of my experience. Surely, the right thing to say is that I am not conscious of the moth.

Since I cannot mentally point to a thing unless I attend to that thing, it follows from the above remarks that seeing a thing demands that one be to attend to that thing (without moving the eyes). This, in turn, entails that there will be cases of things in clear view that one does not see, given where one’s eyes are fixated; for there will often be visible things in the field of view on which one cannot mentally focus, given where one’s eyes are fixated. So, one will be blind to these things. Some cases of change blindness are like this.

Philosophers and psychologists who take change blindness to be a purely cognitive phenomenon as opposed to a failure to see any thing in the field of view often implicitly endorse a clear, colour photograph model for the vehicles of conscious awareness. On this view, in the case of two scenes that differ in one respect, if they are seen one after the other, change blindness arises because an inaccurate comparison is made between the two clear snapshots. There is comparison-failure.

A better model of the vehicles of conscious awareness is provided by drawn pictures. Think about the case of an artist drawing a picture of a scene. The artist begins by fixating on some part of the scene. Some things in the scene are left out of her picture altogether. Others are very richly depicted. We might be a bit like such an artist as we see the things around us. Change blindness then could sometimes arise as a result of certain things not being included in the mental sketch that is drawn of the scene before the eyes. In other cases, it could result from a comparison failure as above.

It is worth noting that the drawn picture model of visual experiences allows for the possibility that some things not in the scene are experienced. Artists sometimes embellish the scenes they draw, adding items that are not present. Upon occasion, we might do that too as we see the world around us.

This general approach extends straightforwardly to other perceptual experiences and it makes a connection, already present in my representationalist view of experience, between consciously perceiving a thing and thinking about it; for, as noted above, one cannot consciously perceive a thing unless what can at least ask “What’s that?” with respect to the thing or form some other de re cognitive attitude with respect to it. So, one cannot consciously perceive a thing unless one can think about (or form a belief or some other cognitive attitude about) it.

3:AM: So Keith Richards is hallucinating a tomato without there being a particular tomato that he is hallucinating. What is the content of his experience? And would it make a difference if it had been a unicorn?

MT: Consider a case of veridical perception. Suppose that Keith is seeing a ripe tomato. The view of naïve realism is that Keith sees the tomato directly. Keith is in direct contact with the perceived object. There is no tomato-like sense-impression that stands as an intermediary between the tomato and him. Nor is he related to the tomato as I am to a pig when I see its footprint in the mud. He does not experience the tomato by experiencing something else over and above the tomato and its facing surface. Keith sees the facing surface of the tomato directly.

Some philosophers have suggested that to do proper justice to the above thought, we need to suppose that the objects we perceive are components of the contents of our perceptual experiences in veridical cases. This supposition is supported further by the simple observation that if I see an object, it must look some way to me, and if an object looks some way to me, then intuitively it is experienced as being some way. On pain of losing direct contact with the object, that again suggests that the object itself figures in the content of the experience, assuming that experience is representational at all.

In cases of illusion, the perceived object appears other than it is. In such cases, intuitively, the perceptual experience is inaccurate. And it is so precisely because the object is not as it appears to be. The simplest explanation of this, it is natural to hold, is that, where there is a perceived object, a perceptual experience has a content into which the perceived object enters along with its apparent properties.

Once it is acknowledged that in veridical and illusory cases the seen object is a component of the content of the experience and thus that the content itself is singular, a puzzle arises. In standard hallucinatory cases there is no object with which the subject is in perceptual contact and correlatively no singular content. So, again, what is the content of Keith’s experience?

One possible answer is that the content is existential in the hallucinatory case. Keith’s visual experience represents that there is something red, round and bulgy before him, and since there is no such thing, his experience is inaccurate. The combination of views that results is unlovely and implausible; for it is forced to postulate a displeasing and radical asymmetry in cases that pre- theoretically seem alike. (My 1995 view that the content of experience is existential in all cases makes the seen object irrelevant to the matching of the experience with the world in the veridical case: all that is needed for the experience to be accurate is that there be some object with so-and-so properties. That now seems to me wrong too. If I see object A, my visual experience – that very experience – would not have been accurate if A had not existed even if some other object that looked just like A had been present.)

Another possible answer is that Keith’s experience has no content at all in the hallucinatory case. Keith is simply sensing a red, round, bulgy sense-datum or he is sensing redly, roundly, and bulgily. Again, the resulting combination of views for the veridical and hallucinatory cases is unlovely and implausible. And there are other well-known difficulties which I shall not rehearse here.

These reflections suggest that in the hallucinatory case, we should say that there is content of the very same sort as in the veridical and illusory cases – content that is just like singular content but with a gap or hole in it where the object is supposed to go. And this is what I said in recent work. However, I have come to think that the very idea of gappy content is incoherent. Let me very briefly sketch the main worry.

Consider the singular content that object O, is red. On the view associated with Bertrand Russell, which I’ll use for illustrative purposes, this content is complex, having object O, and redness as its components. A visual experience (or other mental state) having that content is accurate if and only if O is red. One way to think of the content here – the content that O is red – is as an ordered pair having O as its first member and redness as its second. Another way to think of the content is as a structured, possible state of affairs built out of O and redness.

It was suggested above that where a visual experience is hallucinatory, the content is just like a singular content but with a gap or a hole in it where an object should go. But does this really make sense? On the ordered pair conception of singular content, there must be two items to form the pair. Since a gap or a hole is not an item, or so it seems, there is no first member of the ordered pair and so no ordered pair at all. On the possible state of affairs conception, the relevant complex is structured out of O and redness in the singular case. But in the gappy case, there is no object O. So, how is there a complex entity structured out of its components? There are various things that could be said here on behalf of gappy content but none of them seem to me satisfactory.

Here is another way to think of the content. Consider the thought that Vulcan is a planet. The thought is complex, being composed of the concept Vulcan and the concept planet, combined in a certain way (rather as the sentence “Vulcan is a planet” is composed of the words “Vulcan” and “planet‟ in a certain order). However, the content of the thought need not be complex. The content can be just a set of possible worlds – the set of worlds in which the referent of the concept Vulcan has the property referred to by the concept planet (the property attributed by the thought). Since the concept Vulcan has no referent either in the actual world in any other possible world, the relevant set of possible worlds is empty.

Correspondingly, experiences are complex. They have representational parts. Some parts represent objects seen (if there are any); others represent properties of which the subjects of the experience are conscious. The latter representational parts are arguably more like features (as is the case with real pictures), and so in one sense they are not really parts at all but rather features of parts. But however this is developed further, a complexity in representational structure for experiences need not be reflected in a corresponding complexity in representational content.

Once this point is appreciated, given the difficulties already encountered in trying to understand gappy content, a natural suggestion is that the content of a visual experience is simply a set of possible worlds, namely the set of worlds at which the experience is accurate. On this view, the content of a visual experience is unstructured in the sense that it has no component parts.

This suggestion preserves uniformity in content for all experiences. Experiences, whether they are veridical, illusory, or hallucinatory, have associated with them an appropriate set of possible worlds. An experience, thus, is accurate, if and only if the actual world belongs to the appropriate set of possible worlds. Which is the appropriate set? Answer: the set of worlds at which the objects picked out by representational parts of the experience have the properties the experience aims to attribute to those objects (however this is further cashed out). The objects thus picked out are the objects (if any) that are seen. Where there are no seen objects, as in a hallucination, there are no possible worlds at which the objects picked out by the representational parts of the experience have the experienced properties. So, the set of worlds associated with a hallucinatory experience is the empty set.

It follows that if Keith had been hallucinating a unicorn instead of a tomato, the content of his experience would have been the same, namely the empty set. But, of course, phenomenally – subjectively – the two experiences are very different. On the view being proposed, then, the phenomenal character of an experience is not determined by its representational content. Experiences that are alike in their content can nonetheless differ in their phenomenal character. The thesis of strong content representationalism (that the phenomenal character of an experience is one and the same as its representational content) is, therefore, false. When I wrote Ten Problems of Consciousness, I was a strong content representationalist and I held that the content of visual experience is existential in nature across the board. I no longer hold either view.

3:AM: So there’s an array of formidable philosophers all thinking about what is the nature of consciousness and the mind and qualia and so forth. You’ve all got brains the size of planets. You’ve all read the same papers and know the science. There’s you and Tim Crane and Frank Jackson and Brian McLaughlin and Dan Dennett and Pat Churchland and Jerry Fodor and a whole bunch more and you are all pretty much equals. But you disagree. Given that none of you are any more likely to be right than anyone else, wouldn’t it be rational for you to modify your positions in the light of knowing that your peers disagree? Or are you all trapped in the cognitive illusion that seems to grant reflexive over-confidence?

MT: Planets vary in their sizes… Seriously, the issue that is being raised here is a very difficult and general one within epistemology. It arises whenever there is disagreement among pretty much equals. I leave the answer to this question to the epistemologists.

3:AM: You have actually changed your mind. In your book Consciousness Revisited you argue with your previous self and find new arguments defending materialism. So was there a eureka moment when it suddenly came to you that you were wrong, or was it a gradual slide away from where you used to be, resulting from all the arguments? And as you move forward, are you finding that your thought is still evolving?

MT: The evolution in my thought has been basically as follows. When I wrote Ten Problems of Consciousness in 1995 and Consciousness, Color and Content in 2000, I held these three theses: (1) Common Phenomenal Character: Veridical, illusory and hallucinatory experiences can sometimes have the very same phenomenal character. (2) Common Existential Content: Veridical, illusory and hallucinatory experiences all have existential representational content and in some cases have the very same existential content. (3) Strong Content Representationalism: the phenomenal character of a mental state is one and the same as its poised, nonconceptual, existential content (its PANIC, to use my earlier acronym). I gave up (2) around 2006 (for some reasons, and I held for a while in place of (2): (2a) Disjunctivism about Content: Veridical and illusory experiences have singular contents; hallucinatory experiences have gappy contents.

Since I continued to hold (1), I then also gave up (3) about which I had already started to have independent doubts, since it no longer seemed to me to fit well with the transparency of experience. I can no more be aware (de re) of the content of my current visual experience than I can be aware (de re) of any of intrinsic properties, though I can be aware that I am having a visual experience with such-and-such content.

In place of (3), I adopted: (3a) Strong Property Representationalism: the phenomenal character of an experience is one and the same as the complex of properties represented by the experience. A mental state has phenomenal character just in case it is appropriately poised (a functional role condition) and it nonconceptually represents a complex of properties. I was also then a weak content representationalist: (4) Weak Content Representationalism: necessarily, experiences with the same representational content have the same phenomenal character.

Later, in 2009, I came to have doubts about gappy content and so I gave up (2a) and in its place I accepted: (2b) Common Set-Theoretic Content: Veridical, illusory and hallucinatory experiences have as their content a set of possible worlds. Where there is a seen object A experienced as being F, the relevant set is the set of possible worlds at which A is F. Where there is no seen object (the hallucinatory case), so that ‘A’ is empty, the set of worlds is the set of worlds at which A is F, but this set is now the empty set. (2b) also fits well with my view about the content of thought elaborated in my 2012 book with Mark Sainsbury, Seven Puzzles of Thought. Once (2b) is accepted, weak content representationalism goes. So, now, of the theses above, I hold (1), (2b) and (3a).

The transition in my views has been orderly and (I think) well motivated. As to the future, that’s difficult to predict, but I doubt that I will change my views much from the present ones. Like Russell, however, I have no qualms about changing my mind as the arguments dictate.

3:AM: Finally, if atom by atom my body was replaced by silicon functioning as my current carbon and water stuff, would eventually everything go dark for me, or would my consciousness, my mind, survive?

MT: There are two questions that need to be distinguished here. One is whether the phenomenology would change under the above scenario. It is important to appreciate that this question does not presuppose that the original being still exists at the end of the process. What is being asked is simply whether the phenomenology would change, whoever is the subject of that phenomenology. The second question is whether the original being would survive the process of being gradually siliconised.

In the phenomenology case, the question, as posed, is not: is it metaphysically possible that the phenomenology changes – that it suddenly disappears or changes in its character or alternatively fades away? Rather the question, I take it, is to be understood in the same way as the question: if a rock is dropped, would it fall to earth? The relevant possibility is thus nomological. Similarly, for the case of personal survival.

My view is that the phenomenology would remain unchanged. I argue for this view in a forthcoming essay, available for reading on my webpage, entitled ‘Homunculi Heads and Silicon Chips: The Importance of History to Phenomenology’. The general idea is that none of my beliefs would change, including my beliefs about phenomenology, and it seems very implausible to suppose that the later beliefs would end up being radically mistaken, as would occur if the phenomenology disappeared or changed dramatically. Here I agree with Chalmers. As for the case of personal identity, it’s tricky. One relevant issue is whether my original brain still exists at the end of the gradual replacement process even though the brain at the end is entirely silicon.

3:AM: Are there any books or films that you’ve found helpful to you outside of philosophy?

MT: Not really. Of books with a vaguely philosophical slant, I enjoyed A Fairly Honorable Defeat by Iris Murdoch; as far as films go, Memento and The Matrix.

3:AM: And finally, once everyone has finished reading all your great books, are there five other books you could recommend to the androids here at 3:AM so we can delve further into this fantastic realm of thought?

MT: The Conscious Mind by David Chalmers, The Stream of Consciousness by Barry Dainton, Naturalizing the Mind by Fred Dretske, Perception by Frank Jackson and Zombies and Consciousness by Robert Kirk.

Richard Marshall is still biding his time.

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First published in 3:AM Magazine: Thursday, October 4th, 2012.