COSMIC PHILOSOPHY 



stances. In comparison, we watch the circum- 

 stances as they are varied for us on a great scale 

 by Nature. 



Answering to the two processes of observa- 

 tion and experiment, as Mr. Mill has shown, 

 there are two inductive methods, — the Method 

 of Agreement and the Method of Difference. 

 The former compares different instances of a 

 phenomenon, to ascertain in what respects they 

 agree, while the latter compares an instance 

 of the occurrence of a phenomenon with an in- 

 stance of its non-occurrence, to ascertain in what 

 respects they differ. To cite from Mr. Mill's 

 " System of Logic " a pair of examples, — 

 " When a man is shot through the heart, it is 

 by the method of difference we know that it 

 was the gun-shot which killed him ; for he was 

 in the fulness of life immediately before, all cir- 

 cumstances being the same except the wound." 

 On the other hand, in inquiring into the cause 

 of crystallization, we employ the method of 

 agreement as follows : " We compare instances 

 in which bodies are known to assume crystalline 

 structure, but which have no other point of 

 agreement ; and we find them to have one, and 

 as far as we can observe, only one, antecedent 

 in common, — the deposition of a solid matter 

 from a liquid state, either a state of fusion or 

 of solution. We conclude, therefore, that the 

 solidification of a substance from a liquid state 

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