540 THE POPULAR SCIENCE MONTHLY. 



the Brain," in which lie exposed the unscientific character of the claims 

 of phrenology. In this paper he also extended the idea of reflex 

 nervous function to the centers of sensation and ideation, and enunci- 

 ated the fundamental notions of " consensual " and of " ideo-motor " 

 action. Curiously Mr. Carpenter's arguments converted the author of 

 the book, Dr. Noble, who in a short time surrendered the principal 

 hypotheses which he had endeavored to enforce in it. 



His first systematic work, produced in 1839, was the "Comparative 

 Physiology," or, to cite it by its full title, the "Principles of General 

 and Comparative Physiology, intended as an Introduction to the Study 

 of Human Physiology, and as a Guide to the Philosophical Pursuit of 

 Natural History." This work, which has passed through many edi- 

 tions, and is even now, though out of print, hardly behind the times, 

 is acknowledged to have been when it was first published the best 

 arranged and most clearly written work on physiology in the English 

 language. It was a pioneer and successful effort to deal with the phe- 

 nomena of animal and vegetable life as parts of a single whole in the 

 manner that is now almost universally done in treating of the science 

 of biology. While residing at University Hall, from 1851 to 1859, he 

 remodeled this work and divided it into two parts : the " Comparative 

 Physiology," comprehending the general biological portion ; and the 

 "Human Physiology," consisting of the part relating to the special 

 physiology of man and the higher animals. The " Human Physiology " 

 embodied the most complete and thorough exposition of the subject 

 that had yet been presented, and was particularly remarkable for the 

 manner in which the physiology of the brain and nervous system was 

 treated, and for the introduction of the theories of cerebral localization 

 which have since been elaborated with increasing exactness and re- 

 markable results. The part of the book relating to this branch of the 

 subject, developed and matured by subsequent studies, was published 

 separately in 1874 as the "Principles of Mental Physiology," a book 

 which "Nature," in its review of it, characterized as marking the 

 author as one of those philosophers "who refuse to treat the phe- 

 nomena of mind as though they were in no way connected with the 

 body through which they find their expression." Rejecting the method 

 of treating mental phenomena as abstracted from their surroundings, 

 Dr. Carpenter based his system on the construction and working of the 

 nervous system. "But while shunning the metaphysical system," the 

 reviewer in " Nature " continues, " he does not adopt the other extreme, 

 the doctrine, we mean, of the thorough materialist, who regards all 

 mental phenomena without exception as the outcome of previous phys- 

 ical causes which necessarily produce certain results. He steers a mid- 

 dle course, inasmuch as, while he advances the theory ' of the dependence 

 of the automatic activity of the mind upon conditions which bring it 

 within the nexus of physical causation,' he yet believes in ' an independ- 

 ent power controlling and directing that activity which we call will.' " 



