432 INDUCTION. 



will be found equally true in the phenomena of mind; 

 and even in social and political phenomena, the result 

 of the laws of mind. It is in the case of chemical 

 phenomena that the least progress has yet been made 

 in bringing the special laws under general ones from 

 which they may be deduced ; but there are even in 

 chemistry many circumstances to encourage the hope 

 that such general laws will hereafter be discovered. 

 The different actions of a chemical compound will 

 never, undoubtedly, be found to be the sum of the 

 actions of its separate elements; but there may exist, be- 

 tween the properties of the compound and those of its 

 elements, some constant relation, which if discover- 

 able by a sufficient induction, would enable us to 

 foresee the sort of compound which will result from a 

 new combination before we have actually tried it, and 

 to judge of what sort of elements some new substance 

 is compounded before we have analyzed it : a pro- 

 blem, the solution of which has been propounded by 

 M. Comte as the ideal aim and purpose of chemical 

 speculation. The great law of definite proportions, 

 first discovered in its full generality by Dalton, is a 

 complete solution of this problem in one single aspect 

 (of secondary importance it is true), that of quantity : 



his treatise on General Physiology, in which the highest gene- 

 ralizations which the science of life has yet reached, and the 

 best modern conception of that science as a whole, are exhibited 

 in a manner equally perspicuous and philosophical. On the details 

 of such a treatise the present writer would be an incompetent wit- 

 ness ; these however have been sufficiently vouched for by some 

 of the highest living authorities ; while of the genuinely scientific 

 spirit which pervades it, those may be permitted to express an 

 opinion, who would not be entitled to offer to a work on such a 

 subject, any other praise. 



