4 Need of a Critique. 



And until these questions on the possibility of 

 their science are answered, they should (to ap 

 propriate Kant s language) be solemnly and 

 legally suspended from their present dubious oc 

 cupation. 



It may be objected, however, that we have 

 prejudged the question of the actual existence of 

 ethics as a science in accepting the adverse prima 

 facie evidence drawn from the number and the 

 opposition of ethical theories. The same diver 

 sity, it will be alleged, is found in other sciences 

 whose validity no one thinks of doubting. In 

 fact, putting aside, on the one hand, the purely 

 observational sciences (if there be any, for chem 

 istry is no longer one), in which demonstration 

 has not begun, and, on the other hand, the math 

 ematical sciences, in which it is complete, it will 

 be hard to find any intervening science which is, 

 and has been, wholly exempt from the contradic 

 tions of opposing hypotheses. In natural history, 

 for instance, our own generation has &quot; assisted &quot; 

 at the liveliest disputations concerning the nature 

 and origin of species ; and our fathers witnessed, 

 in the domain of physics, a struggle scarcely less 

 bitter between the corpuscular and the undulatory 

 theories of light. Mathematics even has been 

 in the past the scene of like encounters ; for 



