Philosophy: Body and Mind - Essay Example

Philosophy – Body and Mind According to Block the concept of consciousness is a hybrid concept. In his words. “The word `consciousness con s a number of different concepts and denotes a number of different phenomena. We reason about "consciousness" using some premises that apply to one of the phenomena that fall under "consciousness", other premises that apply to other "consciousnesses" and we end up with trouble” (Block, 1995, 2). In the history of science many parallels can easily be found. For example Aristotle sometimes used the term `velocity to mean average velocity and sometimes to mean immediate velocity. Aristotle actually flailed to find the distinction between average and immediate velocity, and this caused huge confusion in the field of science. Similarly the Florentine Experimenters of the 17th Century used a single word for temperature and for heat, and thereby generated paradoxes. All these cases are very different from the case of consciousness, but there is a similarity, one that they all share with the case of `consciousness. The similarity lies in the fact that in all these cases and in the case of consciousness very different concepts are treated as a single concept. To avoid this kind of mistake Block distinguishes between two kinds of consciousness – phenomenal consciousness which he defined as P- consciousness, and non- phenomenal consciousness, which he defined as access consciousness or A- consciousness. (Block, 1995) To discuss what kind of relation between P- consciousness and A-consciousness Block has portrayed, it is necessary to discuss how he has explained these two types of consciousness. According to Block P-consciousness is a kind of experience. Block suggests that P-conscious properties are experiential properties. Block has defined P-conscious states as some experiential states, i.e. a state can be called P-conscious only if it has experiential properties. He has illustrated the concept of P- consciousness with some examples. An individual is said to have P-conscious states when he can see, hear, smell, taste and have pains. P-conscious properties generally include the experiential properties of sensations, feelings and perceptions. But Block has added some more experimental properties, including thoughts, wants and emotions. According to Block thoughts are P-conscious possibly because it is just a series of mental images or subvocalizations. It is also quite possible that, as block points out, the contents of thoughts themselves have a P-conscious aspect independently of their vehicles. Block points out one crucial thing that a particular trait of P-consciousness that is often missed is that differences in intentional content often make a P-conscious difference. Block claims that P-conscious properties are completely distinct from any cognitive, intentional, or functional property. (Block, 1995) Block also defines A- consciousness. According to him, the non-phenomenal notion of consciousness that is most easily and dangerously conflated with P-consciousness is access-consciousness or A- consciousness. A state is said to be access-conscious or A-conscious “if, in virtue of ones having the state, a representation of its content is (1) inferentially promiscuous, i.e. poised to be used as a premise in reasoning, and (2) poised for [rational] control of action and (3) poised for rational control of speech”. (Block, 1995, 13) Block however says that these three conditions are together sufficient, but not all necessary for the existence of the state of A- consciousness. According to Block (3) is not necessary for the existence of the state of A- consciousness. He regards (3) as unnecessary because he wants to allow non-linguistic animals, e.g. chimps, to have A-conscious states. Block states that A-consciousness is a cluster concept, in which (3) is the element of the cluster with the smallest weight, though it is (3) which often acts as the best practical guide to A-consciousness. (Block, 1995) Block talks about of three main differences between A- consciousness and P consciousness: first, P-conscious content is phenomenal, whereas A-conscious content is representational. Second, A-consciousness is a functional notion, but P-consciousness is not a functional notion. And third, there a thing like a P-conscious type of state. For example the feel of pain is a P-conscious type of state. But any particular kind of thought that is A-conscious at a given time could fail to be accessible at some other time. (Block, 2002) From the above discussion it has become quite clear that Block makes a clear distinction between these two different but related aspects of consciousness that are often confused. But here comes an interesting aspect of Block’s account of consciousness. Although he makes a firm distinction between the two crucial forms of consciousness, he also insists that A-consciousness and P-consciousness interact. Block states that “A- consciousness is an information processing correlate of P-consciousness”. (Block, 2002, 208) This can be illustrated as follows: Suppose individual places huge information into a place what one can refer to as a large workspace of consciousness. When the individual has a particular experience his P-consciousness processes the data in that experience and stores it in that huge workspace of consciousness for making it possible for him to access. For the purposes of giving more simple explanation it may be assumed that this data is stored in tables. It is the situation where Blocks concept of A-consciousness becomes obvious. Here one can find out the need of having A- consciousness. An individual is needed to have A-consciousness for accessing the data that the P-consciousness process has stored in the tables of the huge workspace of consciousness and broadcast this data for open use in the process of reasoning. Although Block claims that P-consciousness and A-consciousness interact, this need not necessarily be the case. If what is just discussed above holds well then P-consciousness temporal location precedes the temporal location of A-consciousness. For P-consciousness to occur A-consciousness need not be the case so there is no reason to suppose that P-consciousness and A-consciousness must interact. If both P-consciousness and A-consciousness were the case, that is they are both temporally apparent, then they only they would interact. If one of either P-consciousness or A-consciousness is not the case, then there is no scope for interaction between the two. According to what that has just been explained above, it is totally possible for P-consciousness to exist without A-consciousness exclusively on the basis that it can occur temporally a bit earlier. Therefore, for P-consciousness to hold A-consciousness need not be the case. In this context some questions would obviously arise, such as for what duration may a P-conscious state exist without there being a correlate A-conscious state? Or is there any real-world example of such a state that supports this view? In case of answering the first question it may well be said that whether duration of the state of P-consciousness existing independent of a correlate A-conscious state is long or short does not matter much, the only thing that is important in this context is the ability for P-consciousness to exist without A-consciousness for any duration. As for a real-world example, suppose a person decided to work in his dining room near his kitchen. During the course of the day he was absorbed in the writing of a long essay and developed a headache. So he stopped work and subsequently became aware that his refrigerator was malfunctioning and producing a high pitched noise. This noise was the factor that had contributed to the development of his headache. Before he developed the headache he was, or at least could have been, P-conscious of the high pitched noise but only upon developing a headache was this A-conscious. Block (1995), however, makes a claim that A-consciousness is quite able to exist independently of P-consciousness. Blocks illustrate the situation with the help of an example. He considers the case of a blindsight patient. Blindsighters can be defined as those people, who have had a part of their visual field damaged to such an extent that they are now blind in that area. This blindsighters are, however, quite accurate in guessing the details of a given property, which is situated in their blind zone, whenever they are asked to identify such a property (Carruthers 2001). According to Block, whenever the blindsighter thinks that that there exists a property in their blind field, his thought would be both A-conscious and P-conscious. However, as far as the state that gives rise to the thought is concerned, Block suggests that this state can only be A-conscious, not P-conscious. (Block, 1995) What Block actually claims is that the blindsighter just knows the content of his blind field without reference to any P-conscious data. If this is true then what is being displayed by the blindsighter is not at all his A-consciousness but something else entirely, the blindsighter is not accessing any content to be broadcast. Maybe the blindsighter is conceptually closed to the P-conscious experience of the property in their visual field and the subsequent A-conscious process simply appears to exist independently of P-consciousness. Whatever the case, Block does not provide a clear explanation of his claim, thereby leaves his position at an uncertain level. To find out whether Block’s claim holds good or not, suppose for a moment that A-consciousness is conceptually possible. If this A-consciousness is considered to be entirely a distinct form of consciousness, which is not at all dependent upon the existence of P-consciousness, then a crucial question arises regarding the role of P- consciousness. If A-consciousness is conceptually possible, if it can exist independently of P-consciousness, if it does all of the conscious work, and finally if A-consciousness is all that is required for anybody to be conscious at functional level, then it would be quite possible for there to exist humans who possess no P-conscious states, but who are functionally equivalent to humans (Silby 1998). They are called zombies. But neither zombie does exist in this world, nor does A-consciousness occur independently of P-consciousness (Rosenthal 1997). A-consciousness can best be defined as an aspect of P-consciousness; it actually depends on P-consciousness for its existence. A-consciousness is merely a process of P-consciousness that can exist only in relation to previous P-conscious states and, importantly, P-consciousness interaction with the huge workspace of consciousness. Therefore, it becomes quite clear that Block is just over extending his argument by claiming that A-consciousness is an distinct form of consciousness and independent of P-consciousness. The distinction that Block makes between the two form of consciousness - P-consciousness and A-consciousness, is, however, quite important. Blocks Outlines certain parameters of the A-state and thus he provides a better picture of a complete consciousness. But if one blindly accepts the claims that Block has made on A-consciousness, then there would exist the possibility of encountering numerous problems such as the functionally equivalent zombie. Therefore, to get the most complete concept of consciousness one needs to consider Block’s explanation, but at the same time has to avoid Block’s liberal position on A-states needs. This way P-conscious states and their subsequently occurrent A-states can be understood, as they actually exist, in relation to one another. References 1. Block, N. (1995). On a confusion about a function of consciousness. Behavioral and Brain Sciences 18 (2): 227-287, available at: http://www.bbsonline.org/Preprints/OldArchive/bbs.block.html (accessed on May 19, 2008) 2. Block, N 2002, Concepts of Consciousness in Chalmers, D (ed.), Philosophy of Mind: Classical and Contemporary Readings, Oxford University Press, Melbourne 3. Carruthers, P. 2001, Higher-Order Theories of Consciousness, in Zalta, E (ed.), The Stanford Encyclopedia of Philosophy (Summer 2001 Edition),Viewed 1 May 2007, . 4. Chalmers, D. 1997, Availability: The Cognitive Basis of Experience, in Block, N Flanagan, O & Guzeldere, G (eds), The Nature of Consciousness, MIT Press, pp. 421-425. 5. Rosenthal, D. 1997. Phenomenal Consciousness and What its Like. Behavioural and Brain Sciences, 20(1): 156-157. 6. Silby, B. 1998, On a Distinction Between Access and Phenomenal Consciousness, Viewed 2 May 2007, . 7. Kihlstrom, J. 1987. The cognitive unconscious. Science, 237:1445-1452. Read More