286 INDUCTION'. 



inTOStlgation iu the important and so eminently imperfect Science of 

 Mind. 



§ 7. The copiousness with which I have exemphfied the discoveiy 

 and explanation of special laws- of phenomena by deduction from sim- 

 pler and more general ones', 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 iiTevo- 

 cably to predominate in the course of scientific investigation from this 

 time forward. A revolution is peaceably and progi'essively 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 reverting from experi- 

 mental to deductive. But the deductions which Bacon abolished were 

 from premisses hastily snatched up, or arbitrarily assumed. The prin- 

 ciples were neither established by legitimate canons of experimental 

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

 jatiohal Deductive Method, verification by specific experience. Be- 

 tween the primitive Method of Deduction and that which I have 

 Attempted to define, there is all the difference which exists between 

 the Aristotelian physics and the Newtonian theory of the heavens. 



That the advances henceforth to be expected even in physical, and 

 still more in mental and social science, will be chiefly the result of 

 deduction, is evident from the general considerations already adduced. 

 Among subjects really accessible to our faculties, those which still 

 remain in a state of dimness and uncertainty (the succession of their 

 phenomena not having yet been brought under fixed and recognizable 

 laws) are mostly those of a very complex character, in Avhich many 

 agents- are at work together, and their effects in a constant state of 

 blending and intermixture. - The disentangling of these crossing threads 

 is a task attended with difficulties which, as we have already shown, 

 are susceptible of solution by the instrument of deduction, alone. 

 !Peduction is the great scientific work of the present and of future 

 ages. The portion henceforth reser\-ed for specific experience in the 

 achievements of science, is mainly that of suggesting hints to be fol- 

 lowed up by the deductive inquijer, and of cQnfirming or checking his 

 conclusions. 



CHAPTER XIV. 



OF THE LIMITS TO THE EXPLAXATIGN OF LAWS OF NATURE ; AND OP 

 HYPOTHESES. 



§ 1. The preceding considerations "have Jed us to recognize a dis- 

 tinction between two kinds of laws, or observed uniformities in nature : 

 ultimate laws, and what may be termed derivative laws. Derivative 

 laws are such as are deducible from, and may, in any of the modes 

 which we have pointed out, be resolved into, other and more general 

 ones. Ultimate laws are those which cannot. We ate not sure that 

 any of the uniformities which we are yet acquainted vvith are ultimate 

 laws ; but we know that there' must be ultimate laws ; and that eYei7 



