INTERMIXTURE OP EFFECTS. 505 



of the speculative faculties in any age in which it is accredited. 

 Nothing can he more ludicrous than the sort of parodies on 

 experimental reasoning which one is accustomed to meet with, 

 not in popular discussion only, but in grave treatises, when 

 the affairs of nations are the theme. &quot; How,&quot; it is asked, 

 &quot; can an institution be bad, when the country has prospered 

 under it?&quot; &quot;How can such or such causes have contributed 

 to the prosperity of one country, when another has prospered 

 without them ?&quot; Whoever makes use of an argument of this 

 kind, not intending to deceive, should be sent back to learn 

 the elements of some one of the more easy physical sciences. 

 Such reasoners ignore the fact of Plurality of Causes in the 

 very case which affords the most signal example of it. So 

 little could be concluded, in such a case, from any possible 

 collation of individual instances, that even the impossibility, 

 in social phenomena, of making artificial experiments, a cir 

 cumstance otherwise so prejudicial to directly inductive inquiry, 

 hardly affords, in this case, additional reason of regret. For 

 even if we could try experiments upon a nation or upon the 

 human race, with as little scruple as M. Magendie tried them 

 on dogs and rabbits, we should never succeed in making two 

 instances identical in every respect except the presence or 

 absence of some one definite circumstance. The nearest 

 approach to an experiment in the philosophical sense, which 

 takes place in politics, is the introduction of a new operative 

 element into national affairs by some special and assignable 

 measure of government, such as the enactment or repeal of a 

 particular law. But where there are so many influences at 

 work, it requires some time for the influence of any new cause 

 upon national phenomena to become apparent; and as the 

 causes operating in so extensive a sphere are not only infinitely 

 numerous, but in a state of perpetual alteration, it is always 

 certain that before the effect of the new cause becomes con 

 spicuous enough to be a subject of induction, so many of the 

 other influencing circumstances will have changed as to vitiate 

 the experiment. 



Two, therefore, of the three possible methods for the study 

 of phenomena resulting from the composition of many causes, 



