عنوان مقاله [English]
نویسنده [English]چکیده [English]
In this paper I explore surprising parallels in the arguments between dualists and materialists in the philosophy of mind in India and the West. In particular, I compare the Nyaya School of India with Cartesian dualism and its Western defenders and the Carvaka School of India with contemporary Western materialists.
Comparative intellectual history is instructive. It can tell us a great deal about the originality of distinctiveness of a particular culture or civilization, and it can tell us when notions are the result of logical trains of thought common to more than one civilization. The comparison of Western and Indian philosophy of mind is instructive in this regard. Although there are some significant differences, India and Western philosophy of mind follow very similar patterns of reasoning and come up with very similar conclusions. Both traditions have contending materialist and dualist traditions, and both sets of arguments have much in common.
The assumption guiding this presentation is that the two traditions had very little contact, and thus the arguments in the two traditions have developed independently. This assumption of independence is important since if influence has occurred between the two traditions we will be able to claim much less about both the nature of each civilization and the universality of certain conceptual moves of philosophical thought. The first point is obvious. The distinctiveness of an intellectual culture is
based on the ideas that have been proposed in it. It does not say much about the mentality of a culture when these ideas are borrowed except that the culture may be receptive to the idea. (This is not always an uninteresting point, however. For
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example, the receptiveness of China to Buddhism has a lot to do with the Taoist framework in place prior to the arrival of Buddhism). It is much more effective to argue for distinctiveness when the ideas the distinctiveness are based on are indigenous.
The universality thesis is similarly imperiled by evidence of borrowing. One cannot argue that certain steps of argument are universal when they have simply been borrowed form a single source. It says nothing about the nature of human thought in general when ideas simply diffuse. It is much more interesting when similar ideas develop independently of each other, particularly in traditions separated in both space and time. The calculus was developed independently by both Leibniz and Newton, but they were working in the same scientific tradition at the same time. Thus they had access to the same antecedents, and were working in the same intellectual milieu. This is not the case for India and European philosophy of mind. Indian philosophy of mind is much earlier and its ideas do not reach the West until after the West develops similar ideas independently. Thus the philosophy of mind offers an excellent test case of the comparative method in intellectual history.
Now it is true that borrowed ideas sometimes become distinctive or integral parts of a mentality. But that isn’t my argument in this paper. If I were discussing Chinese philosophy I might have to deal with the Buddhist influx, but the Indian philosophical tradition is largely independent of outside influences. The key counterargument to my approach is that Indian ideas did in fact reach the West and therefore did influence Western philosophy of mind. There turns out to be some evidence for this as is explained in a paper by Nolan Pliny Jacobson. Jacobson points out that certain ideas, and, in particular, the Buddhist notion of “no-self,” could very well have traveled not only from India to China, which is not in dispute, but from China to France and then to scholars such as David Hume, who spent time in libraries in France and who had read the work of Pierre Bayle, who we know had some familiarity with Buddhist thought. Nevertheless, it is clear that the broad outlines of the debates in the philosophy of mind were already in place prior to this time, with the possible exception of Hume’s ideas about the self, and that the debates carried on even after it was possible for there to have been contact were carried out largely independent of Indian thought.
Interestingly, the philosophy of induction is another area of thought that developed independently in the West and in India. There is little reason to believe there was any influence in this case as the arguments concerning induction did not make the trip from India to China (since Buddhism had little interest in induction) the necessary first step to travel to Europe until later when ideas started to flow straight from India to the West. It is also interesting that two distinct sets of philosophical argument, induction and the self, both make major developments in David Hume while the same topics were treated earlier in India.
I begin with dualism and the self. In Europe, the first important philosopher of mind is, of course, Descartes. Descartes’ status is so well-established, that one type of dualism even carries his name, “Cartesian dualism.” Cartesian dualism involved two substances, material and mental which are distinguished by whether or not they are extended or unextended in space or composed of matter or thought. Descartes was led to this conclusion by the fact that while he could doubt the body, he could not doubt the mind. Western dualism typically regards mental substance as being in time but not space. Further, the self is a thinking substance, and thus is never without thought. To be without thought is, by definition, to be material.
Indian dualism, as represented by Nyaya philosophers such as Gotama, Vatsayana and Uddyotakara, also argue in favor of the self as a substance. Unlike Descartes, who argues for the existence of the self on the basis of the famous cogito, Nyaya philosophers argue (a) from property to substance and (b) from the possibility of memory. Just as a mango is inferred from the properties of the mango, and from the fact that something continues while the properties change, so the self must also be a substance to provide a something for mental properties to inhere in. The Nyaya’s arguments with the Buddhist positions against the self and substance proceed much the same as the Western analogues. Buddhists and Humeans argue that all perception reveals is a stream of perceptions and qualities, never selves or substances, and argue that the inferences from the perceptions to selves and substances are unfounded. Hume and the Buddhists argue that the continuity we seem to perceive in nature is mistaken. Hume tells us that our minds provide us with the continuity of objects and substances of which we really have no direct experience nor any good reason to infer they exist. This is also true of the self. “For my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe any thing but perception.” (Hume, 1975, p.162) Hume is arguing that while we have perceptions of this or that thing, we never have a perception of our self separate from such perceptions. He offers instead a “bundle theory” of the self. The idea is that the self, instead of being a unitary entity, is really a bundle of perceptions that we pull together to form an idea of a continuing self. Hume’s basic view is still extremely popular among materialists and may constitute some sort of orthodoxy in materialist philosophy of mind. In the case both of substance in general and mental substance the Nyaya philosophy infers from properties to substances. One might argue that the Nyaya are similar to Locke in asserting both properties and substances, with a key difference, Nyaya philosophers argue that we actually perceive the mango substance, in the sense that when we see the mango drop we are not merely seeing the properties of mango drop, we are seeing the substance drop as well, whereas Locke merely infers he existence of substance as a bearer of qualities. “For the Nyaya-Vaisesika the substance is not a mysterious entity hiding behind the phenomena. It is perceived and perceived to be different from its qualia. (Chakrabarti, 1999, 80)
Vatsayana argues that memory constitutes a distinct problem for those such as the Buddhists (and by extension, Humeans). “Just as even those who deny the self do not admit that the different states of consciousness abiding in different bodies and restricted to their respective objects cannot have re-cognition, so also (the different state of a stream of consciousness) abiding in the same body cannot have recognition, there being no difference in the two cases.” (Vatsayana, 1967, 73-74) What Vatsayana is arguing is that just as there is no memory of mental life across bodies, memory from one moment to the next in the same body is impossible if there is no on-going self to do the remembering. This same argument was rehearsed by Thomas Reid in the West centuries later. My personal identity, therefore, implies the continued existence of that indivisible thing which I call myself…But perhaps, it may be said, this may be fancy without reality. How do you know—what evidence have you—that there is such a permanent self…which you call yours? To this I answer, that the proper evidence I have of all this is remembrance.” (Reid, 1855, 249) Thus we see both sides of the argument concerning the permanent self occurring in two separate traditions.
The problem with Cartesian dualism is the infamous mind-body interaction problem. If mind and body are so different, how is interaction between the two possible? In fact, they seem defined so that they could not possibly interact. Extended things seem only able to interact with other extended things. Descartes solution, that the interaction takes place in the pineal gland, is not generally taken as even having addressed the problem. Wherever the interaction takes place, there is the problem of something unextended interacting with something extended. The most radical solution to this problem is in the theory known as occasionalism, as proposed by Malebranche, in which mind and body are set in correspondence by God, without any real interaction at all. Because of this seemingly insuperable problem, dualism is seen as deeply problematic in the West as a philosophy of mind.
In contrast to Cartesian dualism, Nyaya philosophy proposes two distinct substances, but, interestingly, distinguishes them a bit differently from Cartesian dualism. The defining characteristic of physical substance for the Nyaya is being the causal substratum of a specific quale that is externally perceivable. (Chakrabarti, 1999, 20) The defining characteristic of physical substance for a Cartesian, as we have seen, is that it is extended, while mental substance is unextended. Nyaya also utilizes the notion of extension in the distinction, but understands extension slightly differently. For the Nyaya, the self is not claimed to be unextended. For a Cartesian, this would seem to make the self another physical substance, but this turns out not to be the case. The Nyaya distinguish two different senses of extension. One sense of extension involves preventing another substance from occupying a space. This is true of physical substance. On the other hand, extension can mean “being in contact with” another substance. While the self is in contact with other substances, it does not prevent them from occupying the same space.
Note that while internal states like cognition are not “in the body” for a Cartesian, the Nyaya can make such a claim based on the idea of contact between mental and physical substance. Internal states (like desire) have location but not extension. The self does have extension in terms of being in contact with a body. Thus Nyaya dualism is not beset by the key problem of Cartesian dualism: the interaction problem. Because mental substance is said to be extended, and therefore not so completely different from physical substance, the idea that mental substance and physical substance can interact is not so obviously problematic. Cartesian dualism simply defines itself into the problem.
Descartes will also have a problem with non-conscious states like sleep or coma, while Nyaya, with its idea of consciousness as a quality of a self rather than composing the self does not have the problem. If the self is composed of thought, and there is no thought, where is the self? If the self is distinct from thought, the lack of thought is merely the lack of a quality of a substance. For Nyaya, consciousness is not the essence of the self. “On the Nyaya view the self alone is the substratum of consciousness; but consciousness or thought is an adventitious quale and originates in the self only when other necessary causal conditions are available.” (Chakrabarti, 1999, 27)
Now does the Nyaya view that mental substance is extended in the sense that it is in space really overcome the interaction problem, or is this just a way of defining away the problem? If we remember, mental substance has extension in the sense of occupying space, but it does not have it in the sense of preventing another substance from occupying it. This raises the problematic issue of contact. Contact is understood to mean “the conjunction of two substances that were previously not in conjunction.” (Chakrabarti, 1999, 24) It isn’t clear that this definition is very helpful, for what is conjunction but contact? Still, one can get a sense of a mental substance in contact with a material substance at location X. Apparently this contact would spread over a certain amount of space, but not in such a way that it would prevent another physical or mental substance from being in contact at the precisely same space. This idea is worth exploring. If two things, A and B, can take up exactly the same space, one wonders what kind of contact that might be. One is tempted to think of a gas mingling with another gas. Or two liquids mixing in a solution. But this analogy cannot be quite right. Gases and liquids don’t really occupy the exact same space. Gas molecules do not share the exact same space with other gas molecules. They move to one side, assuming a compound is not formed via chemical reaction. If something else, B, can enter the exact same space as A, then one wonders what sense it makes to say it is “there.” What is it to touch? Could something, C, come between A and B if A and B are touching?
Contact seems to imply resistance, but this is impossible for a substance that does not prevent another substance from being in the same space. This leads to the uncomfortable realization that maybe the Nyaya concept of mental substance does not overcome the mind-body interaction problem after all. Interaction requires the kind of contact that involves two things that can resist each other. How can one thing affect another unless the contact of the two causes some sort of resistance? Without resistance, how is an effect produced? Now radiation produces effects, but it also provides a form of resistance in affecting the molecules. And a material substance can be irradiated without giving way to another substance, so the analogy works pretty well. One would think that the Nyaya have something like this in mind even though they did not yet have a concept of radiation. But radiation, or energy generally, still isn’t a substance. Nor does it seem to be the right sort of thing to bear mental properties. Although it can be said in favor of the Nyaya position that they don’t immediately define themselves into an interaction problem, the materialists can say even Nyaya dualists have failed to explain mind body interaction.
Nyaya philosophy uses what have come to be known as “privacy arguments” against materialism that are very similar to those used recently. Thomas Nagel has argued that materialism cannot account for first-person experience of qualia, such as what it might be like to be a bat. While materialism can describe, for example, the bat’s echo-location system, it cannot explain what it would be like, especially what it would feel like, to move around using that system. Frank Jackson has argued that materialist accounts cannot account for perceptual knowledge of qualia in the fullest sense since it couldn’t explain the “extra” that is learned when a person who knows all about the theory of the color spectrum but has never seen a color, say red, then comes to actually have the experience of seeing red.
Consider the argument of Vatsayana for psychophysical dualism:
“For this, too, consciousness is not a quale of the body, viz., because of utter dissimilarity from bodily qualia. Bodily qualia are of two types: (1) imperceptible, such as weight, and (2) [externally] perceptible, such as color, etc. But consciousness is of a different type. It is not imperceptible, for it is internally perceptible; not is it [externally] perceptible, for it is grasped by the inner sense. Therefore, it is the quale of a different substance.” (Chakrabarti, 1999, 127) It is clear from this passage that Vatsayana is noticing something similar to what Nagel and Jackson notice, the seemingly categorical difference between perception of external objects and perception of mental states. Vatsayana is here arguing that since consciousness is perceptible, but not externally perceptible, there must be a mental substance to account for this sort of private experience.
Uddyotakara makes a similar argument that is laid out by Chakrabarti in the following steps:
P1: All perceptible physical qualia are perceptible by both oneself and others, for example, color and so on.
P2: No conscious states are perceptible by both oneself and others.
Conclusion: Therefore, no conscious states are perceptible physical qualia. (Chakrabarti, 1999, 133; Nyayavarttika, Uddyotakara, 52) This is more explicitly a Nyaya version of the Western argument from privacy since it refers more clearly to the first person perspective that is unavailable to anyone else. The argument is that no amount of description from the third person perspective can possibly capture the uniqueness of the first person perspective.
The Unitary Self
Another interesting parallel between Indian and contemporary Western arguments in the philosophy of mind has to do with the unitary nature of the self. Consider the “Pervasion Argument” of Vatsayana:
“The body and all the parts of the body are pervaded by the origin of consciousness. There is no part where consciousness does not originate. Since like the body the bodily parts are also conscious, the plurality of cognizers follows as a necessary consequence. In that connection just as the restriction of the awareness of pleasure and pain is a sign for there being different cognizers in each different body, it should have been so in the same body as well. But it is not so; hence consciousness is not a quale of the body.” (Chakrabarti, 1999, 124) Someone like Dennett would simply accept what Vatsayana takes to be the unhappy result. There are bodies with multiple selves, as split brain and MPD experiments show. For example, Chakrabarti writes in explanation of Vatsayana’s argument that “one and the same person is aware of what is happening in different parts of the body. Split brain experiments show that is not necessarily true. Dennett has done a fair amount of work on MPD from a materialist perspective and argues that the self is more of a “narrative center of gravity” than anything like a special type of substance. So Dennett simply has a factual disagreement with Vatsayana. There are sometimes multiple selves in a single body. And sometimes one side of the brain does not have knowledge that the other side of the brain has.
Dead Bodies and Zombies
Another set of parallels arise with the sort of examples anti-materialists come up with in Nyaya and the contemporary West. Let’s call them “Dead body arguments” and “zombie arguments.” Vatsayana asks: “Is consciousness found in the body a quale of the body or is it a quale of some other substance?” (Chakrabarti, 1999, 116)
Vatsayana also writes, “The body is not known to be without color, etc., but is known to be without consciousness, like water which is no longer hot. Therefore, consciousness is not a quale of the body.” (Chakrabarti, 1999, 117)
It is important to note that Vatsayana does not believe heat to be a quale of water, which obviously contradicts modern science’s understanding of heat. Chakrabarti has laid out the argument thus:
P1: All qualia of the body endure as long as the body does, for example, color and the like.
P2: No consciousness states endure as long as the body does.
Conclusion: Therefore, no conscious states are qualia of the body.
In other words, we know of dead bodies in which consciousness does not reside. All the other qualities of the body remain, like color, size etc. There is no non-question-begging reason to distinguish consciousness from other qualia. Therefore, consciousness must inhere in something besides the body.
Interestingly, the Western materialist Paul Churchland makes an argument for materialism that draws on some of the same facts:
P1: We see minds functioning with intact bodies.
P2: Minds function less well or not at all with damage to the body, particularly the brain.
Conclusion: Therefore, the mind is a result of the functions of the brain.
Where is the disconnection between the two arguments? Vatsayana and Churchland draw opposite conclusions from virtually the same facts. The key is in the Nyaya’s refusal to consider consciousness to be a special sort of qualia of the body. Churchland is operating in a physicalist framework in which evolutionism is assumed, and therefore in which new sorts of qualities and abilities can evolve over time in a biologically complex organism. Nyaya is operating in a context in which qualities function with a strict consistency, which isn’t surprising since the only examples of qualities they had to work with were ordinary physical properties and seemingly exception mental properties. They had no knowledge of the possibility of computers, which furnish an example of special sorts of properties arising out of pure matter.
The recent spate of zombie arguments seem to combine elements from the privacy arguments with the Nyaya “dead body” arguments. The zombie arguments of Searle, Chalmers and others invoke the idea of a zombie in order to undermine physicalism in the philosophy of mind. We are to imagine a human being similar in all respects to a normal human except that it has no conscious experience. Such a possibility seems to some to suggest consciousness must be something more than mere brain processes. Since there is a possible world in which all behaviors are the same, but consciousness is missing, that must mean that consciousness cannot be reduced to the functions of physical processes. Such arguments from conceivability are odd to be sure, and I am one who finds them unconvincing; nevertheless, notice that although the point of the two sets of arguments (dead body and zombie) are different, they follow a similar argument pattern, namely to take a normally functioning human body, alter the case with one that is not functioning in some way, and then draw conclusions. The Nyaya method is very similar to contemporary dualists or anti-physicalists. The Nyaya have one key disadvantage compared to modern dualists or epiphenomenalists; they do not have access to modern science. So the Nyaya make the mistake of believing the heat in hot water to be a quale of something besides the water and then drawing an erroneous analogy with the body and consciousness.
Language and Mind
Another key argument dualists draw upon is that the ability to understand language is difficult to account for on materialist grounds. While we already have computers that can simulate conversation, the argument is that such computers do not and can not ever get to the point of understanding language. The most famous such argument is Searle’s Chinese Room “semantic argument.” The idea of the argument is that while a room could be set up to take inputs and give appropriate outputs in such a way as to pass a Turing test of understanding, no real understanding would be taking place, thus showing that a merely syntactic processor can ever be considered capable of thought. We see something similar in the 10th century Nyaya philosopher Jayata Bhatta: “Hearing the letters in succession, understanding the word meanings by way of remembering the semantic connections….understanding the meaning of the sentence as a whole by means of the expectancy and other relationships—these will be very difficult to explain without the self.” (Chakrabarti, 133)
II. The Materialistic Philosophy of Mind and Carvaka Philosophy
The Carvaka view is known almost entirely form texts of its opponents; nevertheless, it is regarded as a distinct school of thought in Indian intellectual history. Carvaka philosophy
is based on a generally materialist metaphysic and an empiricist epistemology. Like most theories of matter in the Ancient world, there are four elements. Radhakrishnan states the Carvaka view in writing, “Intelligence is the modification of the four elements, and it is destroyed when the elements from which it arises are dissolved.” (Radhakrishnan, 1989, 279) Carvaka argues that since we never see a soul existing separately from the body, it must in fact be the body. Mind therefore does not outlive the body. Contemporary materialists such as the Churchlands or Dennett would have no problem accepting this argument. Paul Churchland makes an additional argument that since when we damage the body, particularly the brain, the mind’s functions are impaired or cease. This point would be readily accepted by the Carvaka, and I don’t doubt that if we had more of the Carvaka’s writings we would probably find that very argument.
The key claim of all materialism, ancient and contemporary, Indian and Western, is that mind results from a particular and very special organization of matter. The Nyaya are aware of this argument and respond by pointing out that since the body is made up of things lacking consciousness, then consciousness must be the result of something besides the body. (Chakrabarti, 1999, 135) The Carvaka argue, in effect, that the Nyaya commit the fallacy of composition. Carvakas give a counterexample to support their position. Fermentation produces a drink that is intoxicating from a combination of elements that are not intoxicating.
Carvaka argues that mind does not result merely from combination, but that “consciousness emerges when the material elements are combined in a certain way.” (Chakrabarti, 1999, 118) This is essentially the contemporary materialist view of the mind. We cannot expect much in the way of scientific details, but the general articulation is defensible even today. Vatsayana, however, was aware that the Carvaka physicalist explanation was woefully inadequate and asked the materialists to specify precisely what sort of special combination might yield consciousness. (Chakrabarti, 1999, 143)
Contemporary materialists such as Churchland and Dennett have some answers to Vatsayana, although they would be the first to admit that an acceptable account of this process is years away. Contrasting his own view (the “hardware” or eliminative materialist view) with Dennett’s (the “software” or functionalist view) Churchland writes, “I think Dennett is wrong to see human consciousness as the result of a unique for of ‘software’ that began running on the existing hardware of human brains some ten, or fifty, or a hundred thousand years ago….I shall argue, the phenomenon of consciousness is the result of the brain’s basic hardware structures, structures that are widely shared throughout the animal kingdom, structures that produce consciousness in ….animals just as surely and just as vividly as they produce consciousness in us.”(Catching Consciousness in a Recurrent Net,” (Churchland, 2002,. 64-5) If we therefore distinguish the “software” materialists like Dennett from “hardware” materialists like Churchland, we would have to put the Carvaka in the “hardware” camp.
By contrast with Churchland’s neurobiological treatment of the mind, however, the accounts given by Carvaka seem quaint today. According to Sadananda, there were apparently four schools of materialism, whose primary dispute was over the conception of the soul. These schools identified the soul variously with the whole body, the senses, the breath or with the organ of thought. (Radhakrishnan, 280) There are also accounts as to how intelligence is produced. “That intelligence which is found to be embodied in modified forms of the non-intelligent elements is produced in the same way in which the red colour is produced from the combination of betel, areca nut and lime.”(Sarvasiddhantasarasamgraha, ii. 7, quoted in Radhakrishnan, 279) Radhakrishnan quotes Cabanis, who says “the brain secretes thought as the liver secretes bile.”(Sarvasiddhantasarasamgraha, ii. 7, quoted in Radhakrishnan, 279) These views seem to suggest that intelligence is a property which emerges merely from the combination of certain elements, and possibly that thought itself is material. Mind, of course, requires a very complex organization of matter, not simply the combination of certain types in the right proportions, and thought, whatever it is, is probably not identical with a particular material thing, as the problems with identity theory have shown. Contemporary materialists can draw on the information processing function of computer software to make the notion of intelligence emerging from matter more plausible, and they also have the theory of evolution to help make sense of how intelligence could naturally occur over time as the organization of living matter became increasingly complex. It is a testament to the imagination of the Carvaka that even without this contemporary science they still felt mind could emerge out of matter.
I believe that the above has shown that there is some plausibility to the view that there is a universal logic to the nature of thinking about minds. With the possible exception of the Buddhist no-self doctrine, it is unlikely that these arguments were the result of diffusion. Thus we can have a fair certainty that most of these arguments were developed independently. This implies that even aliens, if we ever encountered them, might very well be vexed by the same concerns, and develop their own sets of materialist and dualist arguments. If a conscious being evolves anywhere, develops knowledge and becomes curious about the nature of mind and intelligence, they will likely end up rehearsing many of the same arguments listed above.