THE EQUILIBRIUM THEORY OF CONSCIOUSNESS 
Professor Herrick’s theory of consciousness, which he frequently 
alluded to in his writings but which he nowhere systematically 
worked out, is bound up with his general view of the dynamic 
nature of the vital equilibrium and its relation to the special func- 
tions of the nervous system. The idea that the living organism is a 
moving balance of equilibrated forces is a familiar idea in recent 
theoretical biology, but this notion has not been extended in any 
thoroughgoing way to the phenomena of brain activity where 
structural and descriptive categories still hold almost exclusive 
sway. 
“In no department of physical science is it so plain as in neurology 
that we are dealing wholly with dynamic elements. While it is true 
that in the structure of the brain we have to do with morphological de- 
tails of marvelous complexity and the descriptive side of our work is con- 
cerned with the varying outlines, sizes, and combinations of cells, fibers, 
etc., and the still more recondite structures within the cells and their 
dendrites, yet it is always obvious that these morphological peculiarities 
are but the expressions of inner forces and their responses to others from 
without. ” “ Correspondence in mode is the condition of identity implied 
by a dynamic theory, and the heterogeneity expressed in the forces of 
the body of a man may be expressed in the terms of the forces of a sper- 
matozoon equally well Does not the body preserve its integ- 
rity in spite of the flux of its materials? Why should not the actual 
materials of the nucleoplasm be in a similar flux while retaining its 
form, i. e., its dynamic attributes?’’ “We venture to suggest that there 
is no such sharp distinction between nervous functioning and the intra- 
cellular processes of the ordinary non-nervous cell as our present termin- 
ology and usage suggest.” There is in the case of many lower types of 
organism “ a form of vital equilibrium so resident in the general system as 
to give rise to much the same phenomena of nervous unity as in the case of 
higher animals. ” “ It, then, may be supposed that the circuit of nervous 
action in any part of the body passes through a variety of smaller somatic 
circuits and that the spheres of the two forms of activity overlap so that 
the return nerve current bears the influence of this interaction. The 
nervous equilibrium is only a central specialized part of a vital equilib- 
rium embracing all the activities of the body.”^^ 
11 “Physiological Corollaries of the Equilibrium Theory of Nervous Action and Con- 
trol/’ Journal of Comparative Neurology, vol. 8, pp. 21-26 (July, 1898). Cf. also 
^‘The Vital Equilibrium and the Nervous System,” Science, June 17, 1898, n. s., 
vol. 7, pp. 813-818. 
12 
