No place in the private world of one observer is identical with a place in the private world of another observer.
 Bertrand Russell, Mysticism and Logic and Other Essays (1910). copy citation

Context

“These belong to different spaces, although, as we shall see, it is possible, with certain limitations, to establish a correlation between them. [154] What we call the different appearances of the same thing to different observers are each in a space private to the observer concerned. No place in the private world of one observer is identical with a place in the private world of another observer. There is therefore no question of combining the different appearances in the one place; and the fact that they cannot all exist in one place affords accordingly no ground whatever for questioning their physical reality.” source