NOVEMBEK 4, 1904.] 



SCIENCE. 



591 



vailing tendency to draw the remarkable 

 conclusion that all facts are somehow 

 mental or experienced facts. The situation 

 Avoiild be worse for psychology than it is, 

 if tliat vigorous science had not learned 

 from other sciences the valuable knack of 

 isolating concrete problems and attacking 

 them directly, without the burden of pre- 

 vious logical or metaphysical speculation. 

 Thus knowledge, which is the peculiar 

 province of logic, is increased, while we 

 wait for the acceptable definition of a 

 mental fact. But definitions, be it remem- 

 bered, are themselves logical matters. 

 Indeed, some psychologists have gone so far 

 as to claim that the distinction of a fact as 

 mental is a purely 'logical' distinction. 

 This is significant as indicating that the 

 time has not yet come for the identification 

 of logic and psychology. 



In refreshingly sharp contrast to the 

 vagueness and uncertainty which beset the 

 definition of a mental fact, are the palpable 

 'eoner.eteness and definiteness of knowledge 

 itself. Every science, even history and 

 philosophy, are instances of it. What con- 

 stitutes a knowledge ought to be as definite 

 and precise a question as could be asked. 

 That logic has made no more progress than 

 it has in the answer to it, appears to be due 

 to the fact that it has not sufficiently 

 grasped the significance of its own sim- 

 plicity. Knowledge has been the important 

 business of thinking man, and he ought to 

 be able to tell what he does in order to 

 know, as readily as he tells what he does in 

 order to build a house. And that is why 

 the Aristotelian logic has held its own so 

 long. In that logic, 'the master of them 

 that know ' simply rehearsed the way he had 

 systematized his own stores of knowledge. 

 Naturally we, so far as we have followed 

 his methods, have had practically nothing 

 to add. In our efforts to improve on him, 

 we have too often left the right way and 

 followed the impossible method inaugurated 



by Locke. Had we examined with greater 

 persistence our own methods of making 

 science, we should have profited more. The 

 introduction of psychology, instead of help- 

 ing the situation, only confuses it. 



Let it be granted, however, in spite of 

 the vagtieness of what is meant by a mental 

 fact, that logical processes are also mental 

 processes. This fact has, as I have already 

 suggested, an important bearing on their 

 genesis, and sets very definite limits to the 

 freedom of thought in creating. It is not, 

 however, as mental processes that they have 

 the value of knowledge. A mental process 

 which is knowledge purports to be con- 

 nected with something other than itself, 

 something which may not be a mental pro- 

 cess at all. This connection should be in- 

 vestigated, but the investigation of it 

 belongs, not to psychology, but to logic. 



I am well aware that this conclusion 

 runs counter to some metaphysical doc- 

 trines, and especially to idealism in all its 

 forms, with the epistemologies based there- 

 on. It is, of course, impossible here to de- 

 fend my position by an elaborate analysis 

 of these metaphysical systems. But I will 

 say this. I am in entire agreement with 

 idealism in its claim that questions of 

 knowledge and of the nature of reality can 

 not viltimately be separated, because we can 

 know reality only as we know it. But the 

 general question as to how we know reality 

 can still be raised. By this I do not mean 

 the question, how is it possible for us to 

 have knowledge at all, or how it is possible 

 for reality to be known at all, but how, as 

 a matter of fact, we actually do know it? 

 That we really do know it, I would most 

 emphatically claim. Still further, I would 

 claim that what we know about it is de- 

 termined, not by the fact that we can know 

 in general, but by the way reality, as dis- 

 tinct from our knowledge, has determined. 

 These ways appear to me to be ascertain- 

 able, and form, thus, undoubtedly a section 



