344 INDUCTION. 



between successive impressions ; and the influence of the law which renders 

 associations stronger in proportion to the pleasurable or painful character 

 of the impressions, being felt with peculiar force in the synchronous class 

 of associations ; it is remarked by the writer referred to, that in minds of 

 strong organic sensibility synchronous associations will be likely to pre- 

 dominate, pi'oducing a tendency to conceive things in pictures and in the 

 concrete, richly clothed in attributes and circumstances, a mental habit 

 which is commonly called Imagination, and is one of the peculiarities of 

 the painter and the poet; while persons of more moderate susceptibility 

 to pleasure and pain will have a tendency to associate facts chiefly in the 

 order of their succession, and such pei'sons, if they possess mental superior- 

 ity, will addict themselves to history or science rather than to creative art. 

 This interesting speculation the author of the present work has endeavored, 

 on another occasion, to pursue further, and to examine how far it will avail 

 towai'd explaining the peculiarities of the poetical temperament.* It is 

 at least an example which may serve, instead of many others, to show the 

 extensive scope which exists for deductive investigation in the important 

 and hitherto so imperfect Science of Mind. 



§ 7. The copiousness with which the discovery and explanation of special 

 laws of phenomena by deduction from simpler and more general ones has 

 here been exemplified, was prompted by a desire to characterize clearly, and 

 place in its due position of importance, the Deductive Method ; which, in the 

 present state of knowledge, is destined henceforth irrevocably to predom- 

 inate in the course of scientific investigation. A revolution is peaceably 

 and progressively effecting itself in philosophy, the reverse of that to which 

 Bacon has attached his name. That great man changed the method of 

 the sciences from deductive to experimental, and it is now rapidly revert- 

 ing from experimental to deductive. But the deductions which Bacon 

 abolished were from premises hastily snatched up, or arbitrarily assumed. 

 The principles were neither established by legitimate canons of experi- 

 mental inquiry, nor the results tested by that indispensable element of a 

 rational Deductive Method, verification by specific experience. Between 

 the primitive method of Deduction and that which I have attempted to 

 characterize, there is all the difference which exists between the Aristotelian 

 physics and the Newtonian theory of the heavens. 



It would, however, be a mistake to expect that those great genei'aliza- 

 tions, from which the subordinate truths of the more backward sciences 

 will probably at some future period be deduced by reasoning (as the 

 truths of astronomy are deduced from the generalities of the Newtonian 

 theory), will be found in all, or even in most cases, among truths now 

 known and admitted. We may rest assured, that many of the most gen- 

 eral laws of nature are as yet entirely unthought of ; and that many others, 

 destined hereafter to assume the same character, are known, if at all, only 

 as laws or properties of some limited class of phenomena; just as electric- 

 ity, now recognized as one of the most universal of natural agencies, was 

 once known only as a curious property which certain substances acquired 

 by friction, of first attracting and then repelling light bodies. If the theo- 

 ries of heat, cohesion, crystallization, and chemical action are destined, as 

 there can be little doubt that they are, to become deductive, the truths 

 which will then be regarded as the principia of those sciences would prob- 



* Dissertations and Discussions, vol. i., fourth paper. • 



