196 
HISTORY OF THE REFLEX THEORY. 
BY G. H. LEWES. 
“ TT is my conviction/* says Professor Bennett, “that wlien 
-H- the bitterness of personal opposition has subsided, the im- 
partial world of science will award to Marshall Hall the honour 
of not only originating, but of establis hin g, and practically 
applying to the treatment of disease, one of the most important 
physiological doctrines discovered since the days of Harvey.”* 
Several other testimonies to the like effect may be read in the 
same volume, which have induced me to write the history of the 
doctrine in question, not only with a view of assigning to 
Marshall Hall his real position, bnt also of adding a chapter to 
the history of our knowledge of the nervous system. As the 
estimate I have been able to form of Marshall Hall is by no 
means of that exalted kind which will constantly be met with 
in the pages of his Memoirs, it may not be wholly superfluous 
to state, that in no sense can “ the bitterness of personal 
opposition ” apply to me, since I never saw the distinguished 
physiologist, nor did I ever come into any personal relation 
with him, direct or indirect. I shall leave it to history to show 
that he did not originate the Reflex Theory, and that, so far 
from having- “ established one of the most important doctrines 
since that of Harvey,” the doctrine has long been given up 
by every physiologist of repute in Europe ; and that the Reflex 
Theory now generally established, positively rejects all that 
Marshall Hall claimed as his discovery. 
What is the Reflex Theory? This is the first point to be 
settled. To state it briefly, we may say, that it is an attempt 
to describe the mechanism by which certain acts in the living 
body take place without consciousness ; and to connect with 
this same mechanism, all those acts in decapitated or brainless 
animals which look like acts prompted by sensation and 
volition, but which cannot be so prompted— it is held — because 
sensation and volition are seated in the brain. If a man be in 
a state of complete unconsciousness, from the pressure of a bit 
of bone on his brain, so that he neither sees, hears, nor feels, 
this cessation of cerebral activity does not prevent his breathing, 
swallowing, &c. The chest expands, the oesophagus contracts 
on being stimulated, the heart beats, the intestines move, — 
these and numerous other nerve-actions go on nearly as well 
* “ Memoirs of Marshall Hall.” By his Widow (p. 117). 
