Sir John Carew Eccles (1903–1997) is, in the neuroscience textbook, the man who elucidated the ionic mechanisms of synaptic excitation and inhibition – Nobel Prize Medicine 1963, jointly with Alan Hodgkin and Andrew Huxley. What is not in the textbook: Eccles was for more than four decades a publicly avowed substance dualist who described the reduction of consciousness to neuronal activity as a "superstition"; was a member of the Pontifical Academy of Sciences; gave the 1977/78 Gifford Lectures in Edinburgh; wrote with Karl Popper the 600-page The Self and Its Brain (Springer 1977); and in 1992, aged 89, published together with the theoretical physicist Friedrich Beck in the Proceedings of the National Academy of Sciences a quantum-mechanical mind-brain interaction model – probably the most concrete neuroscientific variant of the post-1906 programme of Pauli and Bohm. This half of his work appears in no standard neuroscience curriculum.
Who was Eccles?
Born on 27 January 1903 in Melbourne, Australia, son of a school teacher. Medical studies at the University of Melbourne (BSc 1922, MB BS 1925). In 1925 Eccles received a Rhodes Scholarship and went to Magdalen College, Oxford. There he became the student of Charles Sherrington, the founder of modern synaptic theory, who himself received the Nobel Prize a few years later (1932). PhD under Sherrington 1929, Fellow of Magdalen 1932. In 1937 he returned to Australia as Director of the Kanematsu Institute in Sydney, from 1944 Chair of Physiology in Dunedin, New Zealand.
In 1952 he was appointed founding director at the John Curtin School of Medical Research of the Australian National University in Canberra – the 14 years in which the work for which he received the Nobel Prize was carried out. In 1966 he moved to the Institute for Biomedical Research in Chicago, in 1968 to SUNY Buffalo. Retirement 1975, settled in Switzerland (Contra near Locarno) where he lived until his death on 2 May 1997. Knighthood 1958 (KBE), Fellow of the Royal Society 1941, member of the Pontifical Academy of Sciences (appointed 1961, in which Eccles remained active until his death).
The scientific main work: synaptic transmission
The central question that shaped Eccles' scientific career was: How do neurons communicate with each other – electrically or chemically? His teacher Sherrington and Eccles himself long suspected electrical transmission. In a famous scientific debate with Henry Dale and Otto Loewi (advocates of the chemical hypothesis) Eccles had to defend his position into the late 1940s.
The decisive experiments fell in 1951–52. With high-resolution microelectrodes Eccles and his team in Dunedin succeeded in measuring intracellular potentials of single anterior horn motor neurons of the spinal cord. The findings:
- After presynaptic excitation an excitatory postsynaptic potential (EPSP) appears in the receiving neuron – a voltage shift in the expected direction.
- After presynaptic inhibition an inhibitory postsynaptic potential (IPSP) appears – a voltage shift in the opposite direction.
- Both potentials can only be explained by chemical transmission, not by purely electrical means.
Eccles accepted the finding publicly – historians of science describe it as a paradigmatic case of an honest abandonment of a hypothesis – and thereby became the chief architect of contemporary synaptic physiology. In 1963 the Nobel Prize. The citation from the Karolinska Institutet: "for their discoveries concerning the ionic mechanisms involved in excitation and inhibition in the peripheral and central portions of the nerve cell membrane".
The early philosophy: Neurophysiological Basis of Mind (1953)
Already in 1953 Eccles published at Clarendon Press in Oxford a book with a peculiar place in his oeuvre: The Neurophysiological Basis of Mind. The Principles of Neurophysiology. The Waynflete Lectures he had delivered at Magdalen College in 1952. Here Eccles publicly discusses for the first time the question of whether contemporary neurophysiology suffices to explain conscious experience. His answer: no. The structural properties of neuronal activity (spatial distribution, temporal patterns) generate no statement about the qualitative inner side of experience. Eccles was then 50 years old, nine years before his Nobel Prize. The dualist basic conviction was there – not as a late life work but as a continuous position.
Karl Popper and The Self and Its Brain (1977)
Eccles and Karl Popper had known each other since Oxford 1937. Both had independently held the anti-reductionist position, both had become prominent in the 1960s. In the early 1970s they began, at Villa Serbelloni on Lake Como, working on a joint book. Springer-Verlag in Heidelberg published the result in 1977: The Self and Its Brain. An Argument for Interactionism, 600 pages, divided in half between the two authors – Popper wrote the philosophical chapters I–V and the final synthesis, Eccles the empirical chapters VI–X and the detailed neurobiological arguments. The concluding chapters are a verbatim dialogue transcript between the two.
The central thesis is Popper's "three worlds" ontology:
- World 1: the physical-material world (atoms, fields, brains).
- World 2: the world of subjective experiences (consciousness, pain, colour experience).
- World 3: the world of cultural products (libraries, theories, artworks).
Eccles' and Popper's position: these three worlds are ontologically real and causally effective on one another. The brain (World 1) acts on consciousness (World 2), but also conversely: consciousness acts on the brain. This is not epiphenomenalism (in which World 2 exists but does nothing) but interactionism – the direct philosophical line from Descartes, newly formulated.
"I maintain that the human mystery is incredibly demeaned by scientific reductionism, with its claim in promissory materialism to account eventually for all of the spiritual world in terms of patterns of neuronal activity. This belief must be classed as a superstition."
— John Eccles, Evolution of the Brain. Creation of the Self, p. 241 (1989).
The Gifford Lectures 1977/78
In 1977/78 Eccles delivered in Edinburgh the Gifford Lectures, the lecture series running since 1888 explicitly devoted to the "science of Natural Theology" – the question of how far natural-scientific knowledge is compatible with knowledge of God. Lecturers before Eccles had included William James (1900–02), Henri Bergson (1913), Niels Bohr (1949), Werner Heisenberg (1955–56). Eccles' lectures appeared in 1979 from Routledge under the title The Human Mystery, supplemented in 1980 by The Human Psyche.
The central statement of the Gifford Lectures: scientific knowledge does not support materialism but makes it the more untenable the more precisely it describes the brain. The more precisely one clarifies the neuronal mechanisms – and no one has clarified them more precisely than Eccles – the more clearly it becomes apparent that the qualitative inner side of experience is simply not contained in these mechanisms. It must enter differently.
Beck-Eccles 1992: the quantum model of mind-brain interaction
In the late 1980s Eccles faced the hardest problem of his interactionist position: how is the non-material consciousness to influence the material brain without violating the laws of conservation of energy and momentum? Eccles found the answer in quantum mechanics. He took on the Darmstadt theoretical physicist Friedrich Beck as collaborator, who worked out the quantum-field-theoretical details.
In 1992 Beck and Eccles published in the Proceedings of the National Academy of Sciences (PNAS 89, 11357–11361) the paper "Quantum aspects of brain activity and the role of consciousness". The idea in outline:
- At the presynaptic terminals of a nerve cell there are microscopically small structures, the presynaptic vesicular grids – arrayed, stored neurotransmitter vesicles.
- The release of a vesicle (exocytosis) is at the quantum level a statistical tunnelling process with low probability.
- Eccles' hypothesis: non-material consciousness ("World 2") influences this tunnelling probability – not the energy transfer, but the selection of which of the many possible quantum events is actualised. This conserves the energy balance but gives consciousness a causal influence.
- The elementary unit of this influence Eccles calls a psychon – the mental correlate of a dendron, a neuronal micro-site at which the quantum selection takes place.
The paper is not incidental. It is a PNAS main publication by a Nobel laureate at the age of 89, with a detailed quantum-field-theoretical apparatus. It is the most direct neuroscientific variant of the programme that Wigner philosophically opened in 1961 in Remarks on the Mind-Body Question and that Bohm ontologically formulated in 1980 in Wholeness and the Implicate Order. Penrose and Hameroff published their own quantum-mechanical theory of consciousness (Orchestrated Objective Reduction) in 1996 – four years after Beck and Eccles.
How the Self Controls Its Brain (1994)
Two years later, in 1994, Eccles published at Springer-Verlag Berlin his last major work: How the Self Controls Its Brain. A 200-page synthesis of his entire position. Eccles was 91. The book connects the experimental synaptic physiology (his Nobel-Prize work) with the psychon hypothesis (his quantum model) and with the Popperian three-worlds ontology. It is the most compact available presentation of the Eccles programme.
In the preface Eccles writes that the book offers "a comprehensive theory at last attainable, supported by recent neurophysiology and quantum mechanics, of how the non-material conscious self can have effective interaction with neural events at the synaptic level." That is the overall thesis.
Eccles' public confession
Eccles never hid his position. He had been a member of the Pontifical Academy of Sciences since 1961, spoke several times in the Vatican, corresponded with theologians and philosophers, gave popular lectures in the style of his teacher Sherrington. In interviews he described himself as a believer in the immortality of the individual soul. His book The Wonder of Being Human (with the philosopher Daniel N. Robinson, Free Press 1984) is an explicit combination of neurophysiology and religiously informed anthropology.
Notable: unlike Faraday or Maxwell, unlike Jung and Pauli, Eccles held his spiritual-philosophical position quite openly, in the form of English-language standard scientific publishers (Springer, Routledge, Free Press) and at the highest institutional forums (PNAS, Gifford Lectures). Eccles' example proves: it was possible even after 1960 to be a publicly avowed dualist as a Nobel laureate – the cost was not the loss of position but the editorial-receptive decoupling of the spiritual-philosophical half from the "real" scientific work.
Position in the pattern
Eccles is the neuroscientific completion of our post-1906 line. His profile complements the previous cases in two respects:
- Disciplinary: While Schrödinger, Bohm, Pauli and Wigner came from quantum physics, Eccles comes from neuroscience. With this the thesis "consciousness as a methodologically serious quantity" is represented not only from the side of physics but also from the side of biology.
- Concreteness: Eccles and Beck attempted in 1992 to formulate mind-brain interaction in a concrete quantum model with microstructural predictions that are in principle experimentally testable. That is the most operationalisable version of the post-1906 thesis in the entire series.
As with Schrödinger and Bohm: Eccles published. The texts are not hidden. But the editorial-receptive separation takes effect: the Nobel work stands in the textbooks, the dualism and the psychon theory do not. The selection is not forced by the data – it is a historical, institutional fact.
What remains
- Dualism is not refuted. Anyone claiming this must show that the qualitative inner side of experience ("what it is like to see red") follows from the neuronal mechanisms. That demonstration is still pending, ever since Eccles raised the question in 1953. Eccles' Nobel work sharpened the problem; it did not dissolve it.
- The quantum model is published. Beck and Eccles 1992 in PNAS, a peer-reviewed top journal. It has not been refuted; it is not pursued because neuroscience today works largely in the materialist standard direction. But the proposal sits on the table.
- Line to Penrose-Hameroff. The Orchestrated Objective Reduction theory (microtubule consciousness), which Roger Penrose and Stuart Hameroff have published since 1996, is an independent but thematically parallel hypothesis. Penrose in The Emperor's New Mind (1989) explicitly acknowledged Eccles; Beck-Eccles 1992 and Penrose-Hameroff 1996 are two independent, like-directed late-20th-century quantum-mind proposals.
- Eccles was no outsider. Nobel Prize 1963, Royal Society, Pontifical Academy, Gifford Lectures, Springer book with Karl Popper, PNAS publication 1992. Whoever dismisses him as an "esotericist" has not read the institutional record.
- Position in the pattern series. Eccles complements the quantum-physics line (Pauli, Schrödinger, Bohm, Wigner, Dürr, Josephson) on the neuroscientific side. Our post-1906 line now contains both the physics heavyweights and a Nobel-laureate neuroscientist. For the institutional background see our article on Mediumship and Power.
Including Eccles does not mean judging synaptic physiology differently. It means reading it in the theoretical framework in which the man who clarified it embedded it until the end of his life – a framework in which the material brain is the condition but not the producer of consciousness and in which the quantum-mechanical indeterminacy of presynaptic vesicle release provides the only conceivable site at which a non-material self can act on the material brain without violating the conservation laws. Anyone who omits this from the reading reads not Eccles but a reception.
Sources
- John C. Eccles & Karl R. Popper: The Self and Its Brain. An Argument for Interactionism. Springer International, Berlin/Heidelberg/London 1977 – the 600-page main work.
- John C. Eccles: The Neurophysiological Basis of Mind. The Principles of Neurophysiology. Clarendon Press, Oxford 1953 – the Waynflete Lectures, his first systematic statement of the dualist position.
- John C. Eccles: The Human Mystery. Springer, Berlin 1979 – the Gifford Lectures 1977.
- John C. Eccles: The Human Psyche. Springer, Berlin 1980 – the Gifford Lectures 1978.
- John C. Eccles & Daniel N. Robinson: The Wonder of Being Human. Our Brain and Our Mind. Free Press, New York 1984.
- John C. Eccles: Evolution of the Brain. Creation of the Self. Routledge, London 1989 – with the famous "superstition" passage against promissory materialism.
- Friedrich Beck & John C. Eccles: Quantum aspects of brain activity and the role of consciousness. Proceedings of the National Academy of Sciences USA, vol. 89, 1992, pp. 11357–11361.
- John C. Eccles: How the Self Controls Its Brain. Springer, Berlin 1994 – the late synthesis.
- John C. Eccles: Facing Reality. Philosophical Adventures by a Brain Scientist. Longmans, London 1970.
- Ragnar Granit: Charles Scott Sherrington. An Appraisal. Nelson, London 1966 – on the Sherrington context.
- The Australian Academy of Science: Biographical Memoir of Sir John Carew Eccles (Bennett, McKenzie, Stein), 2001.
- Nobelprize.org: John C. Eccles' Nobel Lecture 1963 "The ionic mechanism of postsynaptic inhibition".