In September 1954, forty-seven years after the above words were written, Dr. J. A. V. Bates of the Neurological Research Unit (National Hospital) read his paper, Can Voluntary Movement be Localised in the Cerebral Cortex? to a meeting of the British Association at Oxford. He began by demonstrating, on a number of technical grounds, that the inferences drawn from certain well-known facts of observation are not valid inferences, since those facts do not prove that the so-called motor nerve implements movement in the manner that the theory of two kinds of nerve fibre assumes. We should, he suggested, "cease to regard the cortico-spinal tract as an efferent tract from an area where movements are represented and regard it instead as an afferent tract to a region where they are represented"; and he drew attention to the fact that a similar interpretation of the then observed facts had been brought forward by Francois Franck as long ago as 1886 but had been rejected in favour of Ferrier's hypothesis of efferent and afferent nerve-fibres. See also Observations on the Excitable Cortex in Man by J. A. V. Bates ("Lectures on the Scientific Basis of Medicine" Volume V: 1955-56). 

While engaged on this translation, I ventured to write to the author to enquire after the subsequent fate of what was clearly an attempt (to quote from this section) to "look at the findings of physiology and psychology in the light of the facts themselves, and not, as so often happens in the present-day practice of those sciences, in the light of preconceived opinions and definitions..." I gather from him that it has neither been answered on the one hand, nor accepted on the other. It appears in fact to have been, at least explicitly, ignored as (with the possible exception of pure physics) is evidently the normal practice with scientific interpretations or hypotheses, however well supported experimentally, that are radical enough to interfere with theories so long accepted as to have become embodied in definitions. In his obliging reply to my letter Dr. Bates put the present position as follows: 

"I would say that in the last fifteen years what I referred to as classical hypothesis has come to be held with far less conviction by most of those who are researching in the field, but that it is still taught in text books, and will remain a seductive hypothesis for the beginner, I'm afraid, for many years."

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