Who said this?
Historically the concept of the ‘real’ has been formed in contradistinction to mere ‘illusions’ based on sense deceptions or on other experiences of purely mental origin. There is, however, no fundamental difference between such corrections of one sense experience by others . . . and the procedure employed by the physical sciences when they ascertain that two objects which may to all our senses appear to be alike to not behave in the same way to others. To accept this latter test as the criterion of ‘reality’ would force us to regard the various constructs of physics as more ‘real’ that the things we can touch and see, or even to reserve the term ‘reality’ to something which by definition we can never fully know. Such a use of the term ‘real’ would clearly pervert its original meaning and the conclusion to be drawn from this is probably that it should be altogether avoided in scientific discussion.