On the other hand, some sceptics would assert that the pictures were imaginary, or, at most, founded on mere observations made in the dissecting-room. More acute observers would see that something more than mere invention had been at work, and would suppose that the drawings had been the result of marvellously careful induction, made by comparing the phenomena observed in the dead eye with the symptoms of living patients. At last, in the new civilization, someone living outside the tempest of rival theories, and studying optics for himself, would re-discover the principle of the ophthalmoscope, make one, and actually see living retinas. At once he would perceive that all existing theories alike were provisional working-hypotheses, i.e., mere expressions of ignorance of the essential fact; and that the drawings of the mythical 19th century artists must have been really made by the use of just such an implement as his own.
Now, our discoverer of the future would probably be an aimable man, willing enough to share the joy of his new discovery with whoever desired to possess it; and equally willing to abstain from worrying with it persons who had no such desire. The mental condition of those who erect working-hypotheses into articles of faith, and who like consecrated theories better than Truth, would be too utterly foreign to his conceptions for him to argue with them. As for those who should desire both to retain their theories about the old drawings, and also to use the new instrument, he would consider them differentiated from ordinary lunatics only by not possessing the sincerity of the latter. He would publish an account of his discovery, for the benefit of whoever wished to read about it; and, having done so, would feel he had
