260 INDUCTION AND DEDUCTION. 



To inquiries of this sort no exterior difficulties oppose tliemselves, and, 

 for conducting them, lcno^Yledge and the correct appreciation of relations 

 abundantly suffice; they rarely occur, because the physical inquirer, for 

 most of his problems, does not find ready prepared the thought-material 

 requisite for his mental process ; it should also be remarked that by these 

 our insight into the nature of phenomena is indeed rendered clearer and 

 more thorough, but that the boundaries of science are not thereby 

 enlarged. 



In the great number of other inquiries, the inquirer is confronted by 

 obstacles which, with the whole stock of knowledge furnished by science 

 and with the most perfect powers of discrimination, he cannot remove, 

 and these are new facts or phenomena which pertain to unknown laws, 

 which are not accessible to the understanding from a deficiency of the 

 intervening facts necessary to his ideas. For this class of inquiries there 

 must cooperate, in the case of the philosophical inquirer, something 

 which essentially characterizes his mind, and that is the force of imagin- 

 ation. 



The sum of what we know respecting nature and its forces is, in fact, 

 so small when compared with what Ave do not know respecting them, 

 that the physicists of our times find themselves, in a majority of cases, 

 precisely in the condition of those of the sixteenth century as regards 

 those things which to them were unintelligible but to us are easy ; there 

 is for us, as there was for them, a defect of clearly comprehensible facts 

 essential to the deductive process; in the failure of a single one of these 

 the intellect stands before a chasm which it cannot fill up ; in that ear- 

 lier time the force of imagination was called in aid to an extent which 

 we regard now as wholly inadmissible. The advantage we have over 

 the earlj- inquirers rests therefore not on increased intellectual powers 

 or on the superior delicacy and penetration of our senses, but on a 

 greater affluence of facts or experiences, that is, on an accumulation of 

 materials for the operations of the understanding. Hence there is no 

 doubt to be raised respecting our relative position ; and yet there are 

 but few who have a clear idea of tlie sources from which the constantly 

 increasing store of these materials for thought is derived. 



If we cast a glance backward on the hivStory of the so-called inductive 

 sciences, we at once recognize that for centuries they had the character 

 of an art. Until Kewtou, astronomy and mechanics were arts ; the same 

 were physics until the time of Galileo; and chemistry np to that of Berg- 

 manu. Boerhaave defines chemistry' as the ars doc^ns exercere certas 

 phijsicas operationes. 



Art and science are essentially distinguished from one another by 

 their diiferent aims. * That of art is the search for or the finding 

 of facts; that of science is the explanation of them. By art, of 

 course, we do not here mean any of the fine arts. The artificer seeks to 

 attain an object ; the experimental artificer seeks a thing. From particu- 



*" The aim of art is the discovery of facts ; that of science the discovery of principles 

 and hiws. — J. H. 



