Zadok Paper S100 Winter 1999
The Nature of Humans-Mind and Brain; Body, Soul and Spirit
by Alan Gijspers

Models of mind/brain interface

Goodman describes four different models of the relation between the mind and the brain.60 The first, attributed to Leibnitz, describes a psychophysical parallelism of mind and body, which are ultimately different forms of reality existing in a pre-arranged harmony and with no direct influence on each other. This is discounted by Goodman because it denies the influence of each on the other. The second, dualism, which was championed by Descartes, accepts the idea that mind and body are different essences but that they influence each other. The third, monism, advocated by Hobbes, is that there is no such thing as a non-physical reality, thus mental phenomena do not really exist. There are three sub-sets of this monist theory. The first is that the mental is reducible to the physical, the second that mental phenomena are epiphenomena (secondary, accidental effects to physical processes) and the third that mental phenomena are emergent properties of physical phenomena, the so-called systems theory point of view. The fourth and last model, embraced by Goodman, is the organic unity theory attributed to Spinoza in which physical and mental viewpoints are two ways of seeing the same thing.

A critique of monism is that, as psychological phenomena will in the end be able to be explained in physiological terms, all mind functions can be reduced to biology which in turn can be reduced to physics. In turn all the laws of physics can be systematically connected with and derived from the fundamental laws of matter and motion. Hence, there is nothing in mind functions which will not be able to be reduced to physical equations. Since physics is mechanistic, human behaviour in the end is mechanistic and if mechanistic, determined.

A corollary of this reductionist-materialist position is that in the hierarchy of systems, the higher systems are determined entirely by the lower system, that is that there is bottom-up causation but there is no top-down causation. Non-physical systems cannot influence such a system. Francis Crick in his Astonishing Hypothesis puts it like this: "that 'You', your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more that the behaviour of a vast assembly of nerve cells and their associated molecules".61 Patricia Smith Churchland62 calls for a unified science of the mind/brain in which philosophy will be 'corrected' by such empirical discoveries of the neurosciences.

To: The competing theories

Alan J. Gijsbers MBBS FRACP DTM&H PGDip Epi, is Specialist Physician at Turning Point Drug and Alcohol Centre and at the Department of Drug and Alcohol Studies St Vincent's Hospital. He is a Visiting Physician at the Epworth Hospital, a Senior Lecturer in Clinical Medicine at the Department of Psychological Medicine Monash University and Senior Fellow at St Vincent's Hospital Clinical School, University of Melbourne. He also contributes to a Dual Diagnosis Clinic at the St John of God and St Vincent's Collaborating Centre consulting on people with both Drug and Alcohol and Psychiatric Disorders. He is a fellow ISCAST and editor of their national bulletin. He also somehow manages to be a husband to his wife, Lois, and a father to three children.