116.  Farther, what greatly contributes to make us mistake in this matter is that when we think of the pictures in the fund of the eye, we imagine ourselves looking on the fund of another’s eye, or another looking on the fund of our own eye, and beholding the pictures painted thereon.  Suppose two eyes A and B:  A from some distance looking on the pictures in B sees them inverted, and for that reason concludes they are inverted in B:  but this is wrong.  There are projected in little on the bottom of A the images of the pictures of, suppose, man, earth, etc., which are painted on B. And besides these the eye B itself, and the objects which environ it, together with another earth, are projected in a larger size on A. Now, by the eye A these larger images are deemed the true objects, and the lesser only pictures in miniature.  And it is with respect to those greater images that it determines the situation of the smaller images:  so that comparing the little man with the great earth, A judges him inverted, or that the feet are farthest from and the head nearest to the great earth.  Whereas, if A compare the little man with the little earth, then he will appear erect, i.e. his head shall seem farthest from, and his feet nearest to, the little earth.  But we must consider that B does not see two earths as A does:  it sees only what is represented by the little pictures in A, and consequently shall judge the man erect.  For, in truth, the man in B is not inverted, for there the feet are next the earth; but it is the representation of it in A which is inverted, for there the head of the representation of the picture of the man in B is next the earth, and the feet farthest from the earth, meaning the earth which is without the representation of the pictures in B. For if you take the little images of the pictures in B, and consider them by themselves, and with respect only to one another, they are all erect and in their natural posture.

117.  Farther, there lies a mistake in our imagining that the pictures of external objects are painted on the bottom of the eye.  It hath been shown there is no resemblance between the ideas of sight and things tangible.  It hath likewise been demonstrated that the proper objects of sight do not exist without the mind.  Whence it clearly follows that the pictures painted on the bottom of the eye are not the pictures of external objects.  Let anyone consult his own thoughts, and then say what affinity, what likeness there is between that certain variety and disposition of colours which constitute the visible man, or picture of a man, and that other combination of far different ideas, sensible by touch, which compose the tangible man.  But if this be the case, how come they to be accounted pictures or images, since that supposes them to copy or represent some originals or other?