360 MENTAL FUNCTIONS OF 



We will now consider the special functions of the different 

 parts of the nervous system. 



The mind is evidently the property of the brain ; and the 

 operations of the mind, whether relating to sensation, will, intel- 

 lect, or affections, are evidently the operations of the brain. In the 

 division of this work devoted to general physiology, I proved the 

 brain to be the organ of the mind, as much as the liver is the organ 

 of the secretion of bile ; that what holds good of the function of 

 every other part, holds good of the function of the brain ; and that 

 to ascribe the power of the brain to an immaterial imaginary 

 something called a soul, is a mere hypothesis, the remains of un- 

 enlightened times, and not only unnecessary to the belief of a 

 future state through a divine revelation, but calculated to throw 

 discredit on such revelation, by making its annunciation of a 

 future state appear superfluous. 8 



science, and Lord Bacon's remarks apply to it equally as to astronomical and 

 geological matters ; and I consider that a soul stands upon the same foundation 

 as a centaur or a Briareus. 



* An old argument, which I thought too puerile to notice, and which was 

 disposed of by Gall (1. c. 8vo. t. iii. p. 119. sq.), has just been revived by Lord 

 Brougham to uphold the existence of something called soul distinct from matter. 

 (Paley's Natural Theology, illustrated by Henry Lord Brougham. London, 1835. 

 The body is said to be incessantly changing its constituent particles, so that no 

 part of it is the same after a certain lapse of time ; and yet we feel ourselves to 

 be mentally the same- Now, the change of the particles of the body may be 

 granted. But what then? Do not all the properties of all parts of the body 

 remain the same, as much as its mental character ? are not the fresh particles so 

 assimilated to each part, that all we can see or feel of our bodies, arid the 

 qualities of every part, remain the same, as much as all we observe of the 

 mind, throughout all the changes of particles? Is not a man held to be the 

 same bodily as well as mentally all the days of his life? If the face is marked 

 with the small-pox, do not the pits remain throughout life, though the particles 

 may have all changed ten times ? If a nervous or dyspeptic affection exists here- 

 ditarily, does not the morbid functional peculiarity continue through all the 

 repeated changes of the particles? If a person acquires immunity from small-pox 

 by vaccination, or by having once passed through the disease, is he not in nearly 

 all instances safe against it, though he live long enough to change all his particles 

 again, and again, and again. What is true of all other organs and parts is true, 

 to just the same extent, of the brain, in regard to its substance and its qualities. 



An assertion of Lord Brougham's, that the mind does not decay with the body, 

 but acquires vigour while the body declines, is incorrect. " It is equally cer- 

 tain/' says he, " that while the body is rapidly decaying, between 60 or 63 and 

 70, the mind suffers hardly any IQSS of strength in the generality of men : that 

 men continue to 75 or 76 in the possession of all their mental powers, while few 



