570 LOGIC OF THE MORAL SCIENCES. 



law of human nature, and from the principal outward 

 circumstances (whether universal or confined to par- 

 ticular states of society) which operate upon the 

 human mind through that law, we may be enabled to 

 explain and predict this portion of the phenomena of 

 society, so far as they depend upon that class of cir- 

 cumstances only; overlooking the influence of any 

 other of the circumstances of society; and therefore 

 neither tracing back the circumstances which we do 

 take into account, to their possible origin in some 

 other facts in the social state, nor making allowance 

 for the manner in which any of those other circum- 

 stances may interfere with^ and counteract or modify, 

 the effect of the former. A science is thus constructed, 

 which has received the name of Political Economy. 



The motive which suggests the separation of this 

 portion of the social phenomena from the rest, and the 

 creation of a distinct science relating to them, is that 

 they do mainly depend, at least in the first resort, 

 upon one class of circumstances only ; and that even 

 when other circumstances interfere, the ascertainment 

 of the effect due to the one class of circumstances 

 alone, is a sufficiently intricate and difficult business 

 to make it expedient to perform it once for all, and 

 then allow for the effect of the modifying circumstances : 

 especially as certain fixed combinations of the former 

 are apt to recur often, in conjunction with ever 

 varying circumstances of the latter class. 



Political Economy, as I have said on another occa- 

 sion, concerns itself only with "such of the phenomena 

 of the social state as take place in consequence of the 

 pursuit of wealth. It makes entire abstraction of every 

 other human passion or motive; except those which 

 may be regarded as perpetually antagonising principles 

 to the desire of wealth, namely, aversion to labour, 



