PHYSICAL METHOD. 629 



ences in new cases, it is necessary that the deductive science should stand 

 sentinel over the whole process ; that it should be constantly referred to, 

 and its sanction obtained to every inference. 



The same thing holds true of all generalizations which can be grounded 

 on history. Not only there are such generalizations, but it will presently 

 be shown that the general science of society, which inquires into the laws 

 of succession and co-existence of the great facts constituting the state of 

 society and civilization at any time, can proceed in no other manner than 

 by making such generalizations — afterward to be confirmed by connectihg 

 them with the psychological and ethological laws on which they must 

 really depend. 



§ 6. But (reserving this question for its proper place) in those more special 

 inquiries which form the subject of the separate branches of the social sci- 

 ence, this twofold logical process and reciprocal verification is not possible ; 

 specific experience affords nothing amounting to empirical laws. This is 

 particularly the case where the object is to determine the effect of any one 

 social cause among a great number acting simultaneously ; the effect, for 

 example, of corn laws, or of a prohibitive commercial system generally. 

 Though it may be perfectly certain, from theory, w^iat kind of effects corn 

 laws must produce, and in what general direction their influence must tell 

 upon industrial prosperity, their effect is yet of necessity so much dis- 

 guised by the similar or contrary effects of other influencing agents, that 

 specific experience can at most only show that on the average of some 

 great number of instances, the cases where there were corn laws exhibited 

 the effect in a greater degree than those where there were not. Now the 

 number of instances necessary to exhaust the whole round of combinations 

 of the various influential circumstances, and thus afford a fair average, ne'v- 

 er can be obtained. Not only we can never learn with sufiicient authen- 

 ticity the facts of so many instances, but the world itself does not afford 

 them in sufficient numbers, within the limits of the given state of society 

 and civilization which such inquiries always presuppose. Having thus no 

 previous empirical generalizations with which to collate the conclusions of 

 theory, the only mode of direct verification which remains is to compare 

 those conclusions with the result of an individual experiment or instance. 

 But here the difficulty is equally great. For in order to verify a theory by 

 an experiment, the circumstances of the experiment must be exactly the 

 same with those contemplated in the theory. But in social phenomena the 

 circumstances of no two cases are exactly alike. A trial of corn laws in an- 

 other country, or in a former generation, would go a very little way toward 

 verifying a conclusion drawn respecting their effect in this generation and 

 in this country. It thus happens, in most cases, that the only individual 

 instance really fitted to verify the predictions of theory is the very instance 

 for which the predictions were made; and the verification comes too late 

 to be of any avail for practical guidance. 



Although, however, direct verification is impossible, there is an indirect 

 verification, which is scarcely of less value, and which is always practica- 

 ble. The conclusion drawn as to the individual case can only be directly 

 verified in that case; but it is verified indirectly, by the verification of other 

 conclusions, drawn in other individual cases from the same laws. The ex- 

 perience which comes too late to verify the particular proposition to which 

 it refers, is not too late to help toward verifying the general sufficiency 

 of the theory. The test of the degree in which the science affords safe 



