240 JAMES CLERK MAXWELL. [CHAP. VIII. 



Now since we have here a standard from which deviation may 

 take place, we have, besides the notion of strength, which 

 belongs to force, that of health, which belongs to organic 

 law. Organic beings are not conscious of organic laws, and 

 it is not the conscious being that takes part in them, but 

 another set of laws now appear in very close connexion 

 with the conscious being. I mean the laws of thought. 

 These may be interfered with by organic laws, or by 

 physical disturbances, and no doubt every such interference 

 is regulated by the laws of the brain and of the connexion 

 between that medulla and the process of thought. But the 

 thing to be observed is, that the laws which regulate the 

 right process of the intellect are identical with the most 

 abstract of all laws, those which are found among the 

 relations of necessary truths, and that though these are 

 mixed up with, and modified by, the most complex systems 

 of phenomena in physiology and physics, they must be re- 

 cognised as supreme among the other laws of thought. And 

 this supremacy does not consist in superior strength, as in 

 physical laws, nor yet, I think, in reproducing a type as in 

 organic laws, but in being right and true ; even when other 

 causes have been for a season masters of the brain. 



"When we consider voluntary actions in general, we 

 think we see causes acting like forces on the willing being. 

 Some of our motions arise from physical necessity, some 

 from irritability or organic excitement, some are performed 

 by our machinery without our knowledge, and some evi- 

 dently are due to us and our volitions. Of these, again, 

 some are merely a repetition of a customary act, some are 

 due to the attractions of pleasure or the pressure of con- 

 strained activity, and a few show some indications of being 

 the results of distinct acts of the will. Here again we have 

 a continuation of the analogy of Cause. Some had supposed 

 that in will they had found the only true cause, and that 

 all physical causes are only apparent. I need not say that 

 this doctrine is exploded. 



" What we have to observe is, that new elements enter 

 into the nature of these higher causes, for mere abstract 



