Metaphysical conviction or methodological restriction ? The meaning of John Hughlings Jackson's 'Doctrine of Concomitance' and its usefulness in the past and present

Nicolaas ARTS

Postbus 31187, 6503 CB Nijmegen, The Netherlands


Jackson's 'Doctrine of Concomitance' (DOC) is his answer to the mind-body problem. It consists of three statements: "first, that states of [mind] are utterly different from nervous states; second, that the two things occur together - that for every mental state there is a correlative nervous state; third, that although the two things occur in parallelism, there is no interference of one with the other."(1)

These statements seem to imply that Jackson adopted the view of Leibniz, who believed that mind and brain are so distinct that it is incomprehensible how they could act upon each other. Nevertheless, they progressed along parallel paths and for Leibniz this meant that God arranged things in advance, that He synchronized mind and brain like two clocks.

It is here that the major problem arises in interpreting Jackson's DOC: he did not believe in God or in pre-established harmony. How then could he explain that mind and brain progress along parallel paths? In the past hundred years commentators have tried to solve this problem by claiming that 'in reality' Jackson was a materialist or a Cartesian dualist, but these claims are directly invalidated by Jackson's writings.

Most difficulties with interpreting the DOC originate in a fundamental misunderstanding of what Jackson was up to when he formulated this doctrine. Jackson did not want to defend a philosophical position; he confessed that he did not know and did not care how mind and brain were related; for methodological reasons he just wanted to assume a parallelism.

In this presentation I wish to elaborate on Jackson's strategy in handling the mind-body problem and show how his DOC arose from contemporary discussions about the relation between psychology and physiology, especially in the works of John Stuart Mill, George Henry Lewes and Herbert Spencer.

Moreover, I argue that Jackson's DOC is still a very sensible strategy for dealing with the complexities of the mind-body problem in neurology and psychiatry, albeit for reasons different from those of one hundred years ago.

(1) John Hughlings Jackson - Selected Writings. Edited by James Taylor. London, 1931-1932: Hodder and Stoughton. Reprint: Nijmegen, 1996: Arts & Boeve. Vol. 2, p. 72.


Panel 1A   (Body-Mind)
Tuesday, 14 September 1999

The Neurosciences and Psychiatry: Crossing the Boundaries

Joint Congress of the European Association for the History of Psychiatry (EAHP), the European Club for the History of Neurology (ECHN), and the International Society for the History of the Neurosciences (ISHN)

Zurich and Lausanne, Switzerland, 13-18 September 1999