Modern studies in functions of the human brain have revealed that memory, understanding, reasoning, and imagination are all functions of the brain. Different parts of the brain are seen to possess different functions. The upper part of the brain, cerebrum, is associated with voluntary and conscious properties; the lower part, cerebellum, is associated with unconscious properties.[1] The cerebrum is divided into two hemispheres: the left and the right. The left brain functions are number skills, written and spoken language, reasoning, scientific skills, and right-hand control. The right brain functions are insight, 3-D forms, art awareness, imagination, music awareness, and left-hand control.[2] Damage to any part of the brain can result in an impairment of the particular function associated with that part. Obviously, such a view of brain has led to several philosophical problems like the identity and reality of self, the survival of self, the epistemic certainty of matter-generated ‘truth’, and the possibility of immaterial consciousness.
In his essay, The Story of a Brain,[3] Arnold Zuboff discusses the problems associated with reducing conscious experience to neurophysical processes. He first constructs a fictional case in which a man’s brain is removed from his rottening body and kept in a special nutrient bath connected to some machine that could induce in the brain experiences identical with reality. For instance, to produce an experience of a pond-hole experience, the hypothesis would be: ‘The brain lying in its bath, stripped of its body and far from the pond, if it were made to behave precisely as it naturally would under such pond-hole circumstances, would have for the young man that very same experience.’[4] The first of the problems faced was when the scientists found one morning that the brain of their friend had been split into its two hemispheres by the watchman in his drunkenness. After much discussion, it was finally agreed that the two hemispheres need not be connected at all inorder to restore the normal pattern: each hemisphere in a separate bath could be induced to produce the patterns similar to the connected state; thus, it was opined, the left hemisphere would be induced to behave in a way similar to its receiving impulses from the right hemisphere, and so vice versa. Thus, actual causation was no longer required for the production of the man’s experience of self and the world. And so, separation of the brain hemispheres, it was thought, would not destroy the identity of the self in experience. Later, the problem took a new turn when one scientist replaced a damaged neuron with a fresh one; which brought to surface the assumption that a change in neural identity would not affect the experience of personal unified identity and experience. The whole problem tends in the way to the conclusion that if computers with functions similar to brain could be constructed, then two or three or more computers (without even being synchronized) could be programmed to produce patterns that would give rise to all such computers experiencing a unified self without even knowing what they are in reality and experiencing something quite different from what they really are.
In his paper, The Matrix as Metaphysics,[5] David J. Chalmers revisits the above problem with reference to the movie The Matrix, at the beginning of which Neo ‘thinks that he lives in a city, he thinks that he has hair, he thinks it is 1999, and he thinks that it is sunny outside.’ However, in reality, ‘he is floating in space, he has no hair, the year is around 2199, and the world has been darkened by war.’ In fact, ‘Neo's brain is located in a body, and the computer simulation is controlled by machines rather than by a scientist.’
This matrix hypothesis, according to Chalmers, should be taken seriously. First of all, as Nick Bostrom suggested, it is very well possible that, in future history, technology will evolve that will allow beings to create computer simulations of entire worlds. In a vast number of computer simulations it is possible that there may well be many more beings who are in a matrix (computer simulation of world) than beings who are not. In that case, ‘one might even infer that it is more likely that we are in a matrix than that we are not.’ In fact, it is impossible to know whether we are or are not in a matrix already. The consequences of such a hypothesis are very serious. In Chalmer’s own words:
The Matrix Hypothesis threatens to undercut almost everything I know. It seems to be a skeptical hypothesis: a hypothesis that I cannot rule out, and one that would falsify most of my beliefs if it were true. Where there is a skeptical hypothesis, it looks like none of these beliefs count as genuine knowledge. Of course the beliefs might be true … but I can't rule out the possibility that they are false. So a skeptical hypothesis leads to skepticism about these beliefs: I believe these things, but I do not know them.[6]
Chalmer’s solution to the problem is by showing that the matrix hypothesis is not a skeptical hypothesis but a metaphysical hypothesis. For this he takes help from the creation-hypothesis model that sees this world of experience as created by a being or beings, the computational-hypothesis model that sees computational reality as underlying simulated reality, and the mind-body hypothesis that sees mind and body as separate but interacting realities. As a metaphysical hypothesis the Matrix Hypothesis implies the existence of the external world which is the source of the inputs for simulation of reality. The matrix world is relatively real. However, it may be objected that a simulated world is not real. To this Chalmers replies that it is still clearly possible that a computational level underlies real physical processes. Thus, what is experienced within a matrix also would be reality.
The matrix problem is all dependent on the assumption that conscious reality is determined by the brain. Of course, there are evidences that seem to support this supposition. However, since they are all empirical they are not decisive, being open to falsification. It is very well possible that the assumption that equals brain with mind is false. In that case, the matrix hypothesis would lose ground. Moreover, the matrix hypothesis permits infinite spirals of matrixes. For instance, it is possible that four scientists invent a matrix in which there are four scientists who in turn within that matrix invent a matrix in which are four scientists and so on ad infinitum. However, an infinite spiral of matrixes is a finite impossibility for, with respect to the second law of thermodynamics, there is a limit to useful energy. It may be objected that this sense of a law of thermodynamics is ‘programmed’ into our brain and not really true. In that case then, man himself could not come to know the truth by himself. But if man cannot come to know the truth by himself then how can he know that the proposition ‘man cannot come to know the truth by himself’ is also true? Thus, in order for truth to exist, humans must be free from the deterministic clog of simulators or matter-conditioned consciousness such as the brain.
In that sense, then the Biblical view of man as created in the image of God as a rational, moral, volitional, and spiritual being does better to not only save the phenomena but to also render humans responsible for their choices and actions.
[1] “Brain,” Microsoft Encarta Encyclopedia (Microsoft Corporation, 2001)
[2] Ibid.
[3] Arnold Zuboff, “The Story of a Brain,” The Experience of Philosophy, pp. 382-389
[4] Ibid, p. 383
[5] http://www.u.arizona.edu/~chalmers/papers/matrix.html
[6] Ibid.
© Domenic Marbaniang, Philosophy of Science, 2006
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