Supervenience & Emergentism: A Critical Study in Philosophy of Mind. Rajakishore Nath, Indian Institute of Technology Bombay, India

Transcription

1 Supervenience & Emergentism: A Critical Study in Philosophy of Mind Rajakishore Nath, Indian Institute of Technology Bombay, India Abstract: The paper intends to clarify whether the supervenience theory of mind, with special reference to Kim, can be identified with the emergence theory of mind. Kim s thesis admits that the mental properties are in some sense dependent on the physical properties. Such supervenience might be understood to mean that there cannot be two events alike in all physical respects, i.e. an object cannot alter in some mental respect without altering in the physical respect. My aim in this paper is to clarify that the emergence theory of mind is not identical with the supervenience theory of mind, because emergentism is a non-material theory of mind. This theory maintains that mind or consciousness emerges from material object, but it will not be reducible to that matter. Thus, emergentism is an anti-reductionists theory of mind; and at the same time, it establishes a new order of existence with its special laws of qualities. Keywords: Emergentism, Supervenience, Physical properties, Mental properties, Consciousness, Intentionality. Introduction The paper intends to clarify whether the supervenience theory of mind is identical to the emergence theory of mind. The supervenience thesis admits that the mental properties are in some sense dependent on the physical properties. Such supervenience might be considered to mean that there cannot be two events alike in all physical respects, i.e. an object cannot alter in some mental respect without altering in the physical respect. Kim in one of his research papers on Supervenience 1 argued that there is an identity between both the theses, i.e., the supervenience theory of mind and the emergence theory of mind. He says that the higher level properties notably, consciousness and other mental properties -- emerge when, and only when, an appropriate set of lower level properties are present. In other words, the occurrence of the higher properties is determined by, and is dependent on, the instantiation of appropriate lower-level relations. In spite of this, emergent properties were held to be genuinely novel and characteristically irreducible to the lower level processes from which they emerge. Kim s concept of emergence combines the three components of supervenience delineates, namely, property covariance, dependence, and nonreductive. My aim in this paper is to show that emergence theory of mind is not identical with the supervenience theory of mind, because emergentism is a nonmaterial theory of mind. This theory says that mind or consciousness emerges from material object, but it will not reduce to that matter. In other words, the higher level of quality emerges from the lower level of existence. It emerges therefrom, and does not necessarily belong to that level, but constitutes its possessor a new order of existence

2 with its special laws of qualities. Thus, emergentism as an anti-reductionists theory of mind establishes the toughest of the tough problems of consciousness. The supervenience theory of mind in all hues faces the questions as to how we can account for the qualitative content of our consciousness. It cannot ultimately tell us how the subjective experience is possible or how consciousness can be real in the universe. The Supervenience Thesis The ideas of supervenience have originated in moral philosophy. There are many philosophers like G. E. Moore, R. M. Hare, and many others who describe a dependency relationship between moral properties and non-moral properties that has later been called supervenience. One can speak of supervenience for sentences, facts, events, propositions, and language, but Kim argues that supervenience can be understood in terms of property supervenience. He believes that property supervenience is fundamental and that supervenience for most other entities can be explained in terms of it. Now, one can see that an increasing use of the term supervenience in a varities of ways, indicating the presence of substantial shared intuitive content. For many philosophers, there is a supervenience relation in the domain of the mental on the physical. Accepting or rejecting of the supervenience of the mental on the physical leads to the most basic division between the theories of the mind-body relation theories that accept psycho-physical supervenience are fundamentally materialist, and those that reject it are fundamentally anti-materialist. This difference seems philosophically more basic and more significant than the usual classification of mind-body theories as monist, or dualist. 2 This notion of supervenience, according to Kim, is applicable to Cartesian who combines his belief in the realm of mind disjoint from the material body with the belief that the existence of both mind and body, in spite of their separateness. In this case, the mind is wholly determined once and what goes on in the realm of matter is fixed. This is equivalent in saying that once the distribution of physical properties over the material objects of this world, but one distribution of mental properties over mind. Cartesian is not saying that how things stand with a given mind is fixed by how things stand with a particular material body. But Kim assumes that Descartes is making no assumption whatever as to whether mind is in some way associated, or coordinated with specific material body. Moreover, the notion of supervenience, Davidsion writes, The notion of supervenience, as I have used it, is best thought of as a relation between a predicates S if for every pair of objects such that P is true of one and not of the other there is a predicate of S that is true of one and not of the other. 3 He stresses that all individuals that can be distinguished using the predicate on the supervening level can be distinguished using the predicates on the base level; this does not imply nomological reduction. Supervenience implies monism, but nomological reduction would require the formulation of laws connecting descriptions in terms of the discourse of the base level, which is not possible in the case of mental domain. Here, the very idea of supervenience could be considered to belong to a linguistic or conceptual domain. The main aim of supervenience thesis of mind is to show the following three possible propositions:

3 [Supervenience] mental properties strongly supervene on physical properties. That is, if any system S instantiates a mental property M at t, there necessarily exists a physical property, P, such that S instantiates P at t, and necessarily anything instantiating P at any time instantiating P at any time instantiates M at that time. 4 [Irreducibility] mental properties are not reducible to, and are not identical with physical properties. 5 [Causal efficacy] mental properties have causal efficacy- that is, their instantiations can, and do, cause other properties, both mental and physical, to be instantiated. 6 Kim s own conviction is that the mind-body supervenience thesis maintains that the mental states are not only reducible to but also are supervenient on the physical states in such a way that whatever changes take place in the physical states must make difference to the mental state as well. That is to say that the causal efficacy of the mental is fundamental to our psychological explanation. Therefore, supervenience in the strong-sense makes room for a nomological dependence of the mental on the physical such that the physical states are necessarily responsible for the mental states. Kim characterizes supervenience as a relation of determination, in the sense that fixing the base properties entails fixing the supervenience properties. This dependency relation is interpreted in a strong way that suggests ontological commitment. He says, Central to [the] idea of interconnectedness of things is a notion of dependency (or, its converse determination): things are connected with one another in that whether something exists, or what properties it has, is dependent on, or determined by, what other things exist and what kind of things they are. 7 Kim s strong supervenience theory of mind is identical with type-identity theory but not token-identity. He says, type-physical, which reductively identifies mental properties with physical properties, implies mind-body supervenience. Here, one must notice that the mental is dependent on the physical but not vice versa because the mental states are directly a consequence of the physical states. The mental states do not determine the physical states. In that sense, the mental states remain nomologicaly dependent on the physical universe. Therefore, supervenience is held to have epiphenomenalist implications. Kim s idea of supervenience theory of mind identifies with emergentism as well as with non-reductive physicalism. Kim s thesis makes the mental life supervenient on its physical background. According to Emergent thesis, the mental states are not reducible to but are supervenient on the physical states in such a way that whatever changes take place in the physical states must make a difference to the mental states well. No two things could differ in a mental respect unless they differ in their corresponding physical respect, that is, imperceptibility with respect to physical properties entails indiscernibility with respect to mental properties. This is the core idea of mind-body supervenience. Thus supervenience understood in the strong sense makes room for a nomological dependence of the mental on the physical such that the physical states are necessarily responsible for the mental states. In this sense the mental state remains nomologically dependent on the physical universe according to the thesis of strong supervenience.

4 Supervenience and Emergence There are many philosophers who have identified emergentism theory of mind with supervenience theory of mind because supervenience claim is all that emergentism really accounts for. Kim claims, According to emergentism, higher level properties, notably consciousness and other mental properties, emerge when, and only when, an appropriate set of lower-level basal conditions are present and this means that the occurrence of the higher properties is determined by, and dependent on, the instantiation of appropriate lower-level properties and relations. In spite of this, emergent were held to be genuinely novel characteristics irreducible to the lower level process from which they emerge. Clearly, then, the concept of emergence combines the three components of supervenience, namely, property co-variance, dependence and non-reducibility. In fact, emergenties can be regarded as the first systematic formulation of non-reductive physicalism. 8 Kim s thesis makes the mental life supervenient on its physical condition. That is to say, according to this thesis, the mental states are not reducible to but supervenient on the physical properties in such a way that whatever changes take place in the physical states it affects the mental states as well. Moreover, Kim also admits that emergentism is regarded as the first systematic formulation of non-reductive physicalism. Thomas Nagel claims that, what is needed is something we do not have: a theory of conscious organism as a physical systems composed of chemical elements and occupying space, which also have an individual perspective on the world, and in some cases a capacity for self-awareness as well. In some way that we do not now understand our minds as well as our bodies come into being when these materials are suitably combined and organised. The strange truth seems to be that certain complex, biologically generated physical systems, of which each of us is an example, have rich non-physical properties. 9 According to this thesis, mental properties are not physical properties, yet the Cartesian dualism is false: minds are biological generated physical systems, yet mental properties are nonphysical and come into being. But it is difficult to say that mind-body problem consists in the fact that we do not understand how these claims can all be true. For Nagel, the mind-body problem is not solved by physicalism; rather physicalism is what gives rise to the problem. Furthermore, non-reductive physicalism is characterised into two theses: Distinctness: mental properties are distinct from physical properties Dependence: mental properties are properties of physical objects. 10 The above thesis shows that non-reductive physicalism can be distinguished from the type-identity theory on one hand and Cartesian dualism on the other. As we know that identity theory asserts that mental properties are identical with physical properties, which is the denial of distinctness; and Cartesian dualism asserts that mental properties are properties of mental substance, which is one way of denying dependence. Here, we can assert that the commitment to dependence is what makes non-reductive physicalism physicalism, and the commitment to distinctiveness is what makes it non-reductive. Emergentism was held to be the truth about many non-physical properties by a number of British emergentists like Alexander, Morgan and many other philosophers of late 19 th and early 20 th century. They said that the essential idea of emergentism is

5 that special properties emerge from underlying physical substances, in a way that cannot be predicted or explained from the perspectives of the science of these physical substances. Again, according to emergentists, the laws which determine the emergence of higher-level properties are metaphysically and scientifically basic, in much the same way that fundamental laws of physics are basic; they are unexplained explainers. 11 And this claim is also denied by all forms of physicalism. This is because emergentism holds that mental properties have causal powers which are not explainable in terms of physical substances. But non-reductive physicalism holds that the mental properties are explicable in terms of underlying physical properties. For this reason, it appears important for non-reductive physicalists to deny that mental properties are emergent properties. Although the difference between the two theories is apparent, the notion of emergent property and non-reductive physicalism cannot be adequately drawn on metaphysical grounds. Some properties were claimed to be emergent by the emergentists, and this is what the non-reductive physicalist is supposed to deny. It turns out that on the nonreductionist s view, mental properties are emergent properties too. Once this is recognised, the non-reductive physicalists must accept that whatever problem attached to emergenties attach themselves to non-reductive physicalism too. The above exploration is not acceptable to Kim because of the way he identifies emergentism with supervenience; and at the same time it is bridging the explanatory gap. 12 But the main aim of this paper is to show that the emergence of consciousness or mind to be hard problem of closing the explanatory gap. The Emergence of Consciousness According to emergentism, the higher-level quality emerges from the lower level of existence and has its roots therein, but it emerges there from, and it does not belong to that level but gives rise to a new order of existence with special qualities. Whereas Samuel Alexander says, the higher-level of quality emerges from the lower level of existence and have its roots therein, but it emerges there from, and it does not belong to that lower level, but constitutes its possessor a new order of existence with its special laws of behaviour. The existence of emergent qualities thus described is something to be noted as some would say, under the compulsion of brute empirical fact, or, as I should prefer to say in less harsh terms, to be accepted with the natural piety of the investigator. It admits no explanation. 13 Here emergence refers to the fact that in the course of evolution new things and events occur, with unexpected and unpredictable properties. Things and events are new in the sense in which a great work of art may be described as new. Every genuine emergence introduces novelty into the world. To say that an emergent characteristic is a novel means, firstly, it is not simply a rearrangement of pre-existing elements, although such rearrangement may be one of its determining conditions. Secondly, the characteristic is qualitatively, not just quantitatively, unlike anything that existed before in history. Thirdly, it is unpredictable not only on the basis of knowledge available prior to its emergence but even on the basis of ideally complete knowledge of the state prior to its emergence. These points permit a distinction to be made between what is new in the sense of being a fresh combination of old factors, and what is novel in the sense of being qualitatively unique and unpredictable.

6 Let us now consider how consciousness emerges from material properties, and how the emergent property of consciousness cannot be explained in a functional or computational way. Some philosophers argue that consciousness might be an emergent property, in a sense that it is still compatible with materialism. It is also often held that emergent properties emerging from low-level properties are unpredictable. However, it can be argued that these properties are new in an ontological sense. What is interesting about these properties is that they are not obvious consequences of the low-level properties. But they are still causally supervenient on low-level facts. On the lines of the above argument, we can argue that the phenomenon of consciousness could rise only in the presence of some non-computational physical processes taking place in the brain. We know living human brains are ultimately composed of the same material satisfying the same physical laws as are the inanimate objects of the universe. There is the Cartesian view that consciousness arises only in humans, and that animals are inanimate automata; a view which is clearly preevolutionary. But we have reasons to accept the view that there are lower and higher states of consciousness. Moreover, the most reasonable view seems to be that consciousness is an emergent property of animals arising under the pressure of natural selection. If this is so, then the question is; how does consciousness arise from antecedent conditions in the physical universe? This question is still unanswered. Even the observation of the behaviour of the amoeba creates the strong impression that it is conscious, and we can find symptoms of activity and initiative in its behaviour. That activity and behaviour is something different from what happens in the neurons. The human brain is estimated to have ten thousand millions of neurons, and there are also thousands of synaptic relations among neurons. But, the qualities, which exist in consciousness, are not found in the neuronal relations. There is a new emergent entity in consciousness which did not exist in the neurons. This is because of the emergent properties, consciousness is ontologically new. Now, the question is; why is it that the phenomenon of consciousness appears to occur, as far as we know, only in living beings, although we should not rule out the possibility that consciousness might be present in other appropriate physical systems? The second question is, how could it be that such a seemingly ingredient as non-computational behavior presumed to be inherent in the actions of all material things, so far has entirely escaped the notice of physicists? The first question is related to the subtle and complex organization of the brain, but that alone could not provide a sufficient explanation. Penrose clearly writes, I am contending that the faculty of human understanding lies beyond any computational scheme whatever. If it is microtubules that control the activity of the brain, then there must be something within the action of microtubules that is different from mere computation. 14 Here, he says that this inanimate matter is microtubules that control the activity of the brain because there is life in it (brain). The action of microtubules is different from mere computation because microtubules are conveyer belts inside the cells. They move vesicles, granules, organelles like mitochondria, and chromosomes via special attachment proteins. They also serve a cytoskeletal role, which is completely different from computation. He points out that, such actions are non-computational actions in which life is related to consciousness.

7 The above statement leads to the question, is there any evidence that the phenomenon of consciousness is related to the action of microtubules in particular? It must also be the case that the detailed neural organization of the brain is fundamentally involved in governing what form that consciousness must take. For Penrose, if the detailed neural organization were not important, then our livers would evoke as much consciousness as our brains. He puts it, What the preceding arguments strongly suggest is that it is not just the neural organization of our brains that is important. The cytoskeletal underpinning of those very neurons seems to be essential for consciousness to be present. 15 But it s not a cytoskeleton as such, that is relevant, but some essential physical action that biology has so cleverly contrived to incorporate into the activity of its microtubules. Moreover, it may be pointed out that in our brain there is an enormous organization; and since consciousness appears to be a very global feature of our thinking, it seems that we must look to some kind of coherence on a much larger level than that of single microtubules or even single cytoskeletons. And there is some kind of useful non-computable action involved, which Penrose thinks to be an essential part of consciousness. Secondly, we must expect that vestiges of such noncomputability should also be present, at some indiscernible level, in inanimate matter. But yet the physics of ordinary matter seems to allow no room for such noncomputable behaviour. Again, as we have seen earlier, the basic tenets of non-reductive physicalism is very close to emergentism. In fact, non-reductive physicalism of this variety is best viewed as a form of emergentism. Emergentists in general have accepted purely materialist ontology of concrete physical objects and events. For example, Kim following, Samuel Alexander, one of the principal theoreticians of emergence school, argues that there are mental events over and above neural processes: Alexander says, We thus become aware, partly by experience, partly by reflection, that process with the distinctive quality of mind or consciousness is in the same place and time with a neural process, that is, with a highly differentiated and complex process of our living body. We are forced, therefore, to go beyond the mere correlation of the mental with these neural processes and to identify them. There is but one process which, being of a specific complexity, has the quality of consciousness... It has then to be accepted as an empirical fact that a neural process of a certain level of development processes the quality of consciousness and is thereby mental processes; and, alternatively a mental processes is also a vital one of a certain order. 16 However, the emergentist doctrine that emergent properties are irreducible to the physical conditions out of which they emerge is familiar; this irreducibility claim is constitutive of the emergentist metaphysical world view. Although the emergentists idea of reduction or reductive explanation diverges from the model of reduction implicit in current anti-reductionists argument, the philosophical significance of the denial of reducibility between two property levels is the same. The higher-level properties, being irreducible, are genuinely new additions to the ontology of the world. For example, Samuel Alexander says: Out of certain physiological conditions nature has framed a new quality mind, which is therefore not itself physiological though it lives and moves and has its being in physiological conditions. Hence it is that there can be and is an independent science of psychology No physiological constellation explains for us why it should be mind. 17

8 The supervenience thesis does not bridge the gap between the mental and the physical because it fails to account for how the mental states with their qualitative content arise at all in a material environment. The gap between the physical and mental remains wide because it is not known how the mental world can be explained. Now the question is: Is it not possible that the mental life would not be there even if the physical universe exists perfectly? That is to say, there are possible worlds in which all the physical states of the present universe are present but there is no conscious state at all. For example, robots behave like human beings but lack consciousness. The behaviour itself is not consciousness. And if consciousness is the same in all organisms like material things, there would be no qualitative difference between the human and the non-human. Therefore, we cannot prove that consciousness is supervenient in the physical world. John R. Searle 18 has given an example that will make the above thesis more legitimate. Suppose, we have a system S, and the elements of the system are 1, 2, 3. S might be a stone and the elements might be molecules. There will be features of S that are not, or not necessarily features of 1, 2, 3,... But there are some features which are causally emergent system features. Solidity, liquidity, and transparency are examples of causally emergent system features. In this connection, we should remind ourselves that life is an emergent property and if there were no life, there would be no consciousness either. For example; water is the combination of one oxygen and two-hydrogen molecules. But there are qualitative difference between water on the one hand, and hydrogen and oxygen on the other. The qualities which we find in water, is not the same as oxygen and hydrogen. In the same way, there is a difference between consciousness and matter because there is a qualitative difference between the two. The qualities which emerge from consciousness cannot be explained in the mechanical/functional way; it needs separate explanation, and its explanation is non-reductive explanation. The above discussion shows that consciousness is a causally emergent property of systems. It is an emergent feature of creation systems of neurons in the same way as solidity and liquidity are emergent features of the system of molecules. Though the existence of consciousness can be explained by the causal interactions between elements of the brain at the micro level, consciousness cannot itself be deduced or calculated from the sheer physical structure of the neurons without bringing in some additional account of the causal relations between them. Now the question that arises is: Why is consciousness an irreducible feature of physical reality? There is a standard argument to show that consciousness is not reducible in the way that material qualities are. For example, I am now in a certain conscious state such as pain. Now the question is: what fact in the world corresponds to my statement. I am now in pain? Here is the fact that I have now certain unpleasant conscious sensations, and I am experiencing these sensations from my experience. It is these sensations that are constitutive of my present pain. But the pain is also caused by certain underlying neurophysiological processes consisting in large part of patterns of neuron firing in my brain. If we reduce the first-person sensation of pain to the third-person patterns of neurons firing, then we try to say that the pain is really nothing but the patterns of neurons firings. If this is so, then we are leaving the essential features of pain. No description of the third-person type would convey

9 the first-person character of pain because the first-person features are different from the third-person features. Nagel states this point by contrasting the objectivity of the third-person features with the what-it-is-like features of the subjective states of consciousness. As Nagel points out, 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 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 But fundamentally an organism has conscious mental states if and only if there is something it is like to be that organism something it is like for the organism. 19 Thus I know that I am in pain is a different sort of knowledge than my knowledge that you are in pain. The feeling of pain indicates that there is close relation between consciousness and self-consciousness. This is due to the emergence of self-consciousness out of consciousness and thus making it radically different from what it is, if it is at all human levels. We may point out that the psychological perspective of consciousness is analyzable in terms of phenomenal perspective, but phenomenal consciousness cannot be explained in terms of psychological perspective because of its irreducibility nature. The reductive explanation of consciousness is not possible because consciousness cannot be logically supervening on the physical. This non-reductive aspect of consciousness is naturally supervenient, but not logically supervenient. Chalmers argues that to make the case against reductive explanation, we need to show that consciousness is not logically supervenient on the physical level. In principle, we need to show that it does not supervene globally that is all the microphysical facts in the world do not entail the facts about consciousness. In practice, it is easier to run the argument locally in an individual, microphysical facts in the world do not entail the facts about consciousness. When it comes to consciousness, local and global supervenience plausibly stand and fall together so it does not matter much which we run the argument if consciousness supervenes at all, it almost certainly supervenes locally. If this is disputed, however, all the arguments can be run at the global level with straightforward alterations. 20 This is because the phenomenal property of consciousness makes it different from all other properties. If phenomenal consciousness would have been logically supervenient on the physical body, then it would have been functionally identical with the latter. In that case, consciousness would be explained completely in terms of the physical properties. As Of course, there is a sense in which the physics of the universe must entail the existence of consciousness, if one defines physics as the fundamental science from whose facts and laws everything else follows. This construal of physics, however, trivializes the question involved. If one allows physics to include theories developed specifically to deal with the phenomenon of consciousness, unmotivated by more basic considerations, then we may get an explanation of consciousness, but it will certainly not to be a reductive one. For our purpose, it is best to take physics to be the fundamental science developed to explain observations of the external world. If this kind of physics entailed the facts about consciousness, without invoking consciousness itself in a crucial role, then consciousness would truly be reductively explained. However, there is good reason to believe that no such reductive explanation is possible. Therefore, one cannot reduce facts about consciousness to

10 physical facts and cannot explain the occurrence of consciousness. Therefore, there is little hope that a purely physicalist or materialist theory can explain consciousness at all, especially the phenomenal or qualitative aspects of consciousness. We may say that our knowledge of consciousness comes from our experience and not from external observation. The existence of the external world is not enough for us to assume the existence of conscious experience. It is only the first-person experience of consciousness, which poses the problem of non-reductive in consciousness. Therefore, it is the subjective character of experience, which is not analyzable through any explanatory system of functional states or human behaviour. As Chalmers remarks, if it is logically supervenient, there would be no such epistemic asymmetry, a logically supervenient can be detected straightforwardly and there is no special role for the first person case. 21 The above argument shows that consciousness is a first-person phenomena and cannot be inferred or defined from the neural point. This is because there is gap between neural level and level of conscious experience. Therefore, consciousness cannot be explained reductively, but can be explained in its own terms. This is because the conscious mental states as distinguished from the physical facts have a subjective aspect. For example, the mental state of pain which is not the same as the state of the brain, since the subjective experience of pain is not explainable in terms of the computational functions of the brain. Thus conscious experience cannot be supervenient in terms of neural and functional laws of the brain. When it is not explainable in terms of the brain level, then mind or consciousness cannot be supervenient or dependent on the brain level. This is because of the emergent properties of mind is different from the physical properties. Therefore, these differences between the emergent mental properties of mind and physical properties show that the supervenience theory of mind cannot be identified with the emergence theory of mind. References 1. Kim, Jaegwon (2000), Supervenience, A Companion to the Philosophy of Mind, Samuel Guttenplan (ed.), Blackwell Publishers Ltd., Oxford, p Kim, Jaegwon (1975), Supervenience and Nomological Incommensurables, American Philosophical Quarterly 15, pp Davidson, Donald (1985), Replied to Essays X-XII, Essays on Davidson: Action and Events, Bruce Vermazen and M. B. Hintikka (ed.), Clarendon Press, Oxford, p Kim, Jaegwon (2003), Blocking Causal Drainage and other Maintenance Chores with Mental Causation, Philosophy and Phenomenological Research 67, p Ibid., p Ibid. 7. Kim, Jaegwon (2002), Concept of Supervenience, Supervenience, J. Kim (ed.), Dartmouth Publishing Company, England, p. 53.

11 8. Kim, Jaegwon (2000), Supervenience, A Companion to the Philosophy of Mind, Samuel Guttenplan (ed.), p Nagel, Thomas (1985), The View from Nowhere, Clarendon Press, Oxford, p Crane, Tim (2000), The Significance of Emergence, Physicalism and its Discontents, Barry Loewer and Grant Gillett (ed.), Cambridge University Press, Cambridge. See in details to this webpage: Retrived on 14 th of September, Horgan, Terence (2002), From Supervenience to Superdupervenience: Meeting the Demands of a material world, Supervenience, J. Kim (ed.), pp See Thomas Nagel (1998), What Is It Like to Be a Bat, The Nature of Consciousness, Ned Block, Owen Flanagan, and Guiven Guzeldere (ed.), The MIT Press, Massachusetts. 13. Alexander, S. (1927, Second Edition), Space, Time, and Deity, Vol.II, The Humanities Press, New York, (also published in Macmillan, London, 1950), pp See the internet source: Retrived on 14 th September Penrose, Roger (1995), Shadows of the Mind, Oxford University Press, Oxford, p Ibid., p Alexander, S. (1927, Second Edition), Space, Time, and Deity, Vol.II, pp Ibid., p Searle, John R. ( 1994), The Rediscovery of the Mind, The MIT Press, Cambridge, Mass., p Nagel, Thomas (1998), What Is It Like to Be a Bat, The Nature of Consciousness, Ned Block, Owen Flanagan, and Guiven Guzeldere (ed.), The MIT Press, Massachusetts, p Chalmers, David J. (1996), The Conscious Mind, Oxford University Press, Oxford, p Ibid., p.98.