Hostname: page-component-76fb5796d-vfjqv Total loading time: 0 Render date: 2024-04-26T12:56:45.453Z Has data issue: false hasContentIssue false

Physicalism and the Evolution of Consciousness

Published online by Cambridge University Press:  01 January 2020

Roland Puccetti*
Affiliation:
Dalhousie University
Get access

Extract

The proper study of Mankind is animal evolution. If one looks back on the evolutionary time-scale one finds all kinds of animals surviving in our midst which have very simple nervous systems and whose behaviour amounts to little more than a stereotyped running off of genetically stored behavioural routines. On the other end of this scale, and including man, are animals with large nerve ganglia, or brains, who are far less dependent upon what is already in the genotype, far more capable of selective attention to incoming stimuli and able to lay down new neural connections in accordance with their experience: in a word, largely self-adaptive creatures. Such animals—the more highly evolved birds and all mammals—give much the same kind of evidence of being conscious as one's fellow men do. One is naturally tempted to suppose that consciousness, correlated as it seems to be with possession of a complex nervous system and self-adaptive behaviour, has some selective advantage for evolution of higher animals: if it does not, then how is it we are conscious?

Type
Research Article
Copyright
Copyright © The Authors 1975

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 See: Wooldridge, Dean E., The Machinery of the Brain (McGraw-Hill Paperback, 1963),Google Scholar Chapter 5.

2 See: Thorpe, W. H., “Ethology and Consciousness,” in Brain and Conscious Experience, ed. Eccles, J. C. (New York: Springer-Verlag, 1966)Google Scholar, Chapter 19.

3 It is often overlooked by those who counsel agnosticism on the issue of sub-human animal consciousness (e.g., Eccles in the discussion of Thorpe's paper, op. cit.) that primitive Cartesianism opens the door to solipsism: perhaps I am the only animal with a soul. Human-like speech can hardly be a necessary condition of consciousness; no one would say the infant child or the aphasic is unconscious.

4 It is because they are fairly regular that we are able to label irregular associations (e.g., being whipped and feeling lust) ‘perverse'.

5 See: Shaffer, Jerome A., Philosophy of Mind (Englewood Cliffs, N.J.: Prentice-Hall, Inc., 1968),Google Scholar Chapter 2, for a similar point in another connection.

6 The Mind-Brain Identity Theory (London and New York: Macmillan and St. Martin's Press, 1970), p. 29.

7 One of the co-founders of the theory, Smart, J. J. C., rejects this description for the reason that if two things are in fact identical they cannot be said to be correlated: “You cannot correlate something with itself” (“Sensations and Brain Processes,” The Philosophical Review, LXVIII, No.2 (April 1959], 142)Google Scholar. But of course one needs the correlation before one can claim the identity.

8 However it is not denied by proponents of this version that banishing psychological language from ordinary discourse would be in the highest degree impractical (see: Rorty, Richard, “Mind-Body Identity, Privacy, and Categories,The Review of Metaphysics, XIX [1965]Google Scholar, reprinted in Borst, op. cit., especially pp. 194 and 198-199.)

9 Brandt, Richard and Kim, Jaegwon, “The Logic of the Identity Theory,The Journal of Philosophy, LXIV, No. 17 (September 7, 1967)Google Scholar.

10 See, e.g., J. D. French, “The Reticular Formation,” Scientific American (May 1957). Reprinted in Scientific American reprint no. 66.

11 See, e.g., Goldenson, R. M., “Somnambulism,” in The Encyclopedia of Human Behavior (New York: Doubleday). II, 1240·1241Google Scholar. Contrary to popular belief, sleep-walkers do fall down stairs or step in front of moving cars, so obviously they are not attentive to essential incoming stimuli.

12 Huxley, T. H., “On the Hypothesis that Animals are Automata and Its History,” (1874), reprinted in The Problems of Philosophy, ed. Alston, William P. and Brandt, Richard B. (Boston: Allyn and Bacon, Inc., 1967), pp. 403414Google Scholar. Huxley's argument was drawn from a study by E. Mesne!, De I'Automatisme de Ia Mémoire et du Souvenir dans le Somnambulisme Pathologique, of a French sergeant who apparently had part of his left parietal lobe destroyed by a Prussian bullet. It is ironical that Huxley thought this case supported Epiphenomenalism, since the unfortunate soldier was able to do what he did only at the cost of conscious disconnection from his environment.

13 Andersson, Bengt, “The Physiology of Thirst,” in Progress in Physiological Psychology (New York and London: Academic Press, 1966), I, 193194Google Scholar.

14 Actually the preoptic region and lateral hypothalamus of the goat brain, when stimulated, produce the same ‘drinking reflex'. But this is no problem for PSI: a single generic P-event can have multiple spatial locations in the brain.

15 It hardly could: not more than a small fraction of neuronal firings in the mammalian brain is accompanied by conscious experience, for important reasons to be discussed in the next section of this paper.

16 See, e.g., the statement by D. M. Armstrong in “The Nature of Mind,” reprinted as amended in Borst (op. cit.), that “In fact the verdict of modern science seems to be that the sole cause (italics mine-RP] of mind-betokening behaviour in man and the higher animals is the physico-chemical workings of the central nervous system” (p. 73).

17 See, e.g., Rorty (op. cit., pp. 192·193), where he says: “The absurdity of saying, 'Nobody has ever felt a pain’ is no greater than that of saying ‘Nobody has ever seen a demon', if we have a suitable answer to the question ‘What was I reporting when I said I felt a pain?“'

18 A particularly lucid semi-popular account is provided in Calder, Nigel, The Mind of Man (London: BBC Publications, 1970)Google Scholar”. Chapter 8. I have used his example of learning to use a spoon (pp. 150-153) in what follows.

19 I have profited from discussion of earlier versions of this paper with David M. Armstrong (by correspondence), Jonathan Bennett, Jaegwon Kim (by correspondence), David Braybrooke and several other colleagues at Dalhousie.