By the aid of the touch, then, we have associated the visual phenomena with thing which are _not_ the organ of vision; and well it is for us that we have done so betimes, and before we were aware of the eye's existence. Had the eye been indicated to us in the mere act of seeing; had we become apprised of its existence _before_ we had associated our visual sensations with the tangible objects constituting the material universe, the probability, nay the certainty, is that we would have associated them with this eye, and that then it would have been as impossible for us to break up the association between colours and the organ, as it now is for us to dissolve the union between colours and material things. In which case we should have remained blind, or as bad as blind; brightness would have been in the eye when it ought to have been in the sun; greenness would have been in the retina when it ought to have been in the grass. A most wise provision of nature it certainly is, by which our visual sensations are disposed of in the right way before we obtain any knowledge of the eye. And most wisely has nature seconded her own scheme by obscuring all the sources from which that knowledge might be derived. The light eyelids--the effortless muscular apparatus performing its ministrations so gently as to be almost unfelt--the tactual sensations so imperceptible when the eye is left to its own motions, so keen when it is invaded by an exploring finger, and so anxious to avoid all contact by which the existence of the organ might be betrayed. All these are so many means adopted by nature to keep back from the infant seer all knowledge of his own eye--a knowledge which, if developed prematurely, would have perverted the functions, if not rendered nugatory the very existence of the organ.