THE PRACTICAL CHARACTER OF REALITY 245 



to assert, is just what a 'real thing' means (at least, this is one 

 of the meanings of 'real'), a thing good for something else in 

 the way of experience. To experience a thing as real is to 

 experience it as having reference to that which is not contained 

 in the experience itself. And here we come into open contra- 

 diction with immediatism. For this is precisely what the things 

 of immediate experience are not, good for anything else in the 

 way of experience, provided that things experienced are, indeed, 

 the experiences themselves. 



To put the matter otherwise, the 'real,' I should say, is never 

 immediately experienced at all; it is always ideal. This being 

 so, it turns out that all experiences are not equally good at tell- 

 ing what the nature of a thing really is. If they were, there 

 would be no such thing as illusions at all. In the case of the 

 Zollner lines, the visual experience is not as good as an experi- 

 ence of measuring for telling whether the lines really are con- 

 vergent or not. Perhaps the question may arise: If 'con- 

 vergent' means 'meeting in a point when produced,' what is 

 meant by seeing lines 'as convergent' when they do not actually 

 meet? Simply that a certain visual appearance, now recognized, 

 has come to be a sign or symbol of other experiences. Indeed, 

 the association of these experiences with this visual appearance 

 is so close, that 'convergent' is often used to denote the visual 

 appearance without explicit reference to the possible extension 

 of the convergent lines to a meeting-point. Thus in the illusion 

 we do, as Professor Dewey says, see real convergence, in the 

 sense that we do actually experience this visual appearance. But 

 let the question arise, whether the lines are really convergent or 

 not; and the reference is no longer to the visual appearance 

 alone, but to the possibility of actually extending the lines until 

 they meet, or of applying some other recognized test of con- 

 vergence. It is this ambiguity in the meaning of 'convergent' 

 which, it seems to me, makes plausible the contention of Pro- 

 fessor Dewey, that the lines of the Zollner illusion are really 

 convergent. And there is, I believe, a similar ambiguity in the 



