494 THE POPULAR SCIENCE MONTHLY 



propositions and on the historical possibility of their being true when 

 applied to the conditions of a society of the past. Again the certainty 

 of the result will depend on the assurance that the historian has dis- 

 covered all the conditions, and this will always remain an open question. 

 The reverse process, so popular with sociologists and psychologists, is 

 also of some service. By the collection of the data of individual acts 

 and striking an average, the personal volitional element can be approxi- 

 mately eliminated, and the residue over and above the probable conduct 

 reveals a partial cause of the activities of the masses. Besides the 

 meager data which the past affords and the impossibility of sending 

 elaborate questionnaires to past generations, both of which facts hinder 

 the use of this method, the results reached by such means show only 

 the general tendency, the probable action, and not the particular acts 

 and motives which form such a prominent feature of history. 



The true method of history would seem to be the canon of con- 

 comitant variations; but unfortunately there is no invariable measure, 

 as in the physical sciences, by which variations can be mathematically 

 determined. All elements of social life vary continually. If we select 

 one as a measure for all, we may be using that which is most variable 

 and certainly one of the causes of variations in other elements of society. 

 In fact a social yard-stick is wanting. In the study of primitive society 

 this canon has been employed successfully because of the large number 

 of similar phenomena, both past and present, but it fails to satisfy the 

 needs of the historian of a civilized people. 



By this hasty review of the canons of inductive reasoning, it is 

 seen that only two, and these the least desirable, can be employed by the 

 historian, and then with very material limitations. History is not a 

 science of pure induction and never can be. The facts of history could 

 never be joined into causal relations by induction alone. If there were 

 no other means, history would remain chronology. 



How then can causal relations be established by the historian ? The 

 answer is : " By deductive and teleological reasoning, for the most part 

 by the latter." 



The past illustrates the operation of the laws which have been estab- 

 lished by the social sciences. The method of deduction can be em- 

 ployed in cases where individual volition can be eliminated, where 

 causes psychological or economic affect large masses of individuals, 

 bringing about important historical changes. In tracing economic 

 development and social psychic life this method establishes causes which 

 satisfy the mind and a large mass of historical knowledge is thus re- 

 moved from the charge of uncertainty. 



As a rule, however, the historian's view of the past is teleological. 

 "We are obliged to pass from effect to cause just as we do when reviewing 

 our own lives. Knowing the end reached by human society at any 

 period, we trace back the events which have been the means of bringing 



