Page:Ferrier's Works Volume 3 "Philosophical Remains" (1883 ed.).djvu/371

Rh points to be not in the same plane? Certainly not. If the points are not in the same plane, we learn this too from a very different experience than that of sight. All that we see is, that the points are out of one another; and this simply implies the perception of extension, without implying the perception either of plane or of solid extension. Thus, by the observation of a very obvious fact, which, however, Mr Bailey has overlooked, is Berkeley's assertion that visible objects are apprehended as extended, and yet not apprehended either as planes or solids, relieved from every appearance of contradiction.

It must, however, be admitted that Mr Bailey has much to justify him in his opinion that extension must be apprehended either as plane or as solid. None of Berkeley's followers, we believe, have ever dreamt of conceiving it otherwise; and, finding in their master's work the negation of solid extension specially insisted on, they leapt to the conclusion that the Bishop admitted the original perception of plane extension. But Berkeley makes no such admission. He places the perception of plane extension on precisely the same footing with that of solid extension. "We see planes," says he, "in the same way that we see solids." And the wisdom of the averment is obvious; for the affirmation of plane extension involves the negation of solid extension, but this negation involves the conception (visually derived) of solid extension; but the