SECT. 10.] Chance, Causation, and Design. 245 



one remarks that that was the very house in which he was 

 born. We begin to wonder if this was an odd coincidence 

 and nothing more. But if our informant goes on to tell us 

 that the house was an old family one, and was occupied by 

 the brother of the deceased, we should feel at once that 

 these facts put the matter in a rather different light. Or 

 again, as Cournot suggests, if we hear that two brothers 

 have been killed in battle on the same day, it makes a great 

 difference in our estimation of the case whether they were 

 killed fighting in the same engagement or whether one fell 

 in the north of France and the other in the south. The 

 latter we should at once class with mere coincidences, whereas 

 the former might admit of explanation. 



10. The problem, as thus conceived, seems to be one 

 rather of Inductive Logic than of Probability, because there 

 is not the slightest attempt to calculate chances. But it 

 deserves some notice here. Of course no accurate thinker 

 who was under the sway of modern physical notions would 

 for a moment doubt that each of the two elements in question 

 had its own cause behind it, from which (assuming perfect 

 knowledge) it might have been confidently inferred. No 

 more would he doubt, I apprehend, that if we could take a 

 sufficiently minute and comprehensive view, and penetrate 

 sufficiently far back into the past, we should reach a stage at 

 which (again assuming perfect knowledge) the coexistence of 

 the two events could equally have been foreseen. The 

 employment of the word casual therefore does not imply any 

 rejection of a cause ; but it does nevertheless correspond to a 

 distinction of some practical importance. We call a coinci 

 dence casual, I apprehend, when we mean to imply that no 

 knowledge of one of the two elements, which we can suppose 

 to be practically attainable, would enable us to expect the 

 other. We know of no generalization which covers them 



