430 INDUCTION. 



fundamental distinctions in nature. The former case, 

 that of the Composition of Causes, is the general one ; 

 the other is always special and exceptional. There 

 are no objects which do not, as to some of their phe- 

 nomena, obey the principle of the Composition of 

 Causes ; none that have not some laws which are 

 rigidly fulfilled in every combination into which the 

 objects enter. The weight of a body, for instance, is 

 a property which it retains in all the combinations in 

 which it is placed. The weight of a chemical com- 

 pound, or of an organized body, is equal to the sum 

 of the weights of the elements which compose it. 

 The weight either of the elements or of the compound 

 will vary, if they be carried farther from their centre 

 of attraction, or brought nearer to it ; but whatever 

 affects the one affects the other. They always re- 

 main precisely equal. So again, the component parts 

 of a vegetable or animal substance do not lose their 

 mechanical and chemical properties as separate agents, 

 when, by a peculiar mode of juxta-position, they, as 

 an aggregate whole, acquire physiological or vital pro- 

 perties in addition. Those bodies continue, as before, 

 to obey mechanical and chemical laws, in so far as the 

 operation of those laws is not counteracted by the 

 new laws which govern them as organized beings. 

 When, in short, a concurrence of causes takes place 

 which calls into action new laws, bearing no analogy 

 to any that we can trace in the separate operation of 

 the causes, the new laws may supersede one portion 

 of the previous laws but coexist with another portion, 

 and may even compound the effect of those previous 

 laws with their own. 



Again, laws which were themselves generated in 

 the second mode, may generate others in the first. 

 Though there be laws which, like those of chemistry 



