62.  Now, that there is no necessary connexion between these two distinct extensions is evident from hence:  because our eyes might have been framed in such a manner as to be able to see nothing but what were less than the Minimum TANGIBILE.  In which case it is not impossible we might have perceived all the immediate objects of sight, the very same that we do now:  but unto those visible appearances there would not be connected those different tangible magnitudes that are now.  Which shows the judgments we make of the magnitude of things placed at a distance from the various greatness of the immediate objects of sight do not arise from any essential or necessary but only a customary tie, which has been observed between them.

63.  Moreover, it is not only certain that any idea of sight might not have been connected with this or that idea of touch, which we now observe to accompany it:  but also that the greater visible magnitudes might have been connected with, and introduced into our minds lesser tangible magnitudes and the lesser visible magnitudes greater tangible magnitudes.  Nay, that it actually is so we have daily experience; that object which makes a strong and large appearance, not seeming near so great as another, the visible magnitude whereof is much less, but more faint, and the appearance upper, or which is the same thing painted lower on the retina, which faintness and situation suggest both greater magnitude and greater distance.

64.  From which, and from sect. 57 and 58, it is manifest that as we do not perceive the magnitudes of objects immediately by sight, so neither do we perceive them by the mediation of anything which has a necessary connexion with them.  Those ideas that now suggest unto us the various magnitudes of external objects before we touch them, might possibly have suggested no such thing:  or they might have signified them in a direct contrary manner:  so that the very same ideas, on the perception whereof we judge an object to be small, might as well have served to make us conclude it great.  Those ideas being in their own nature equally fitted to bring into our minds the idea of small or great, or no size at all of outward objects; just as the words of any language are in their own nature indifferent to signify this or that thing or nothing at all.

65.  As we see distance, so we see magnitude.  And we see both in the same way that we see shame or anger in the looks of a man.  Those passions are themselves invisible, they are nevertheless let in by the eye along with colours and alterations of countenance, which are the immediate object of vision:  and which signify them for no other reason than barely because they have been observed to accompany them.  Without which experience we should no more have taken blushing for a sign of shame than of gladness.