THE NA TURE OF DEA TH. 7 1 



and constitution, or in the same state or condition, nor in 

 any case can an "ultimate molecule" be a subject of de- 

 monstration. An authority may make vague statements of 

 this kind, and may even gain for them the support of friends 

 who may be determined to accept his doctrine as an article 

 of belief; but science cannot be in any way advanced by 

 such operations, nor can knowledge be increased. 



Any one who has brought himself to believe in " the 

 utter inseparability of one particle of living force from the 

 matter in which it has been placed" will, I think, be ready to 

 admit his inability to state the grounds of his belief. The 

 author of this sentence seems to have confused himself, for 

 he speaks of a "particle of living force" being " placed in" 

 matter. If the matter and force be inseparable, how can 

 the latter have been placed in the former, for does not the 

 possibility of placing in imply previous separation, if not 

 subsequent separability ? 



Dr. Bence Jones desires that his readers should believe 

 that living force is ordinary force, and that there is no force 

 or power, spirit or energy separable from the living thing, 

 any more than from the non-living thing. By the accept- 

 ance of such a conclusion it is supposed that the great 

 end of ensuring the preservation of the " unity of nature " 

 will be gained. 



Correlation is the "abracadabra" of mechanical biology. 

 Of late years the term " differentiation " which was formerly 

 much employed in explanation of biological difficulties, 

 and was once the talisman supposed to solve every con- 

 structive mystery, has been degraded to a very subordinate 

 position. The phenomena formerly supposed to be due to 

 " differentiation " are now regarded as the result of correla- 



