LAST EFFORTS OF LOGISTICIANS. 179 



it is true, but you make mistakes too." For us, making 

 mistakes is a misfortune, a very great misfortune, but 

 for you it is death. 



Neither must you say, " Does the infalHbility of arith- 

 metic prevent errors of addition ? " The rules of calcula- 

 tion are infallible, and yet we find people making 

 mistakes through not applying these rules. But a 

 revision of their calculation will show at once just 

 where they went astray. Here the case is quite dif- 

 ferent. The logisticians have applied their rules, and 

 yet they have fallen into contradiction. So true is 

 this, that they are preparing to alter these rules and 

 "sacrifice the notion of class." Why alter them if 

 they were infallible ? 



" We are not obliged," you say, " to solve hie et nunc 

 all possible problems." Oh, we do not ask as much as 

 that. If, in face of a problem, you gave no solution, 

 we should have nothing to say ; but, on the contrary, 

 you give two, and these two are contradictory, and 

 consequently one at least of them is false, and it is 

 this that constitutes a failure. 



Mr. Russell attempts to reconcile these contradic- 

 tions, which can only be done, according to him, " by 

 restricting or even sacrificing the notion of class." 

 And M. Couturat, discounting the success of this 

 attempt, adds: "If logisticians succeed where others 

 have failed, M. Poincare will surely recollect this sen- 

 tence, and give logistic the credit of the solution." 



Certainly not. Logistic exists ; it has its code, which 

 has already gone through four editions ; or, rather, it 

 is this code which is logistic itself Is Mr. Russell 

 preparing to show that one at least of the two contra- 

 dictory arguments has transgressed the code ? Not in 



