to see us: therefore, as water is shed around them, so a dense air is around us. But we desire nothing better. What? do you suppose that a mole longs for light?—nor would he complain to the god that he could not see far, but rather that he saw incorrectly. Do you see that ship? It appears to us to be standing still; but to those who are in that ship, this villa appears to be moving. Seek for the reason why it seems so, and if you discover it ever so much, and I do not know whether you may not be able to, still you will have proved, not that you have a trustworthy witness, but that he has not given false evidence without sufficient reason.
XXVI. What need had I to speak of the ship? for I saw that what I said about the oar was despised by you; perhaps you expect something more serious. What can be greater than the sun, which the mathematicians affirm to be more than eighteen times as large as the earth? How little does it appear to us! To me, indeed, it seems about a foot in diameter; but Epicurus thinks it possible that it may be even less than it seems, but not much; nor does he think that it is much greater, but that it is very near the size it seems to be: so that our eyes are either quite correct, or, at all events, not very incorrect. What becomes then of the exception, “If once . . .?” However, let us leave this credulous man, who does not believe that the senses are ever wrong,—not even now, when that sun, which is borne along with such rapidity that it is impossible even to conceive how great its velocity is, nevertheless seems to us to be standing still.
However, to abridge the controversy, consider, I pray you, within what narrow bounds you are confined. There are four principles which conduct you to the conclusion that there is nothing which can be known, or perceived, or comprehended;—and it is about this that the whole dispute is. The first principle is, that some perceptions are false; the second, that such cannot be perceived; the third, that of perceptions between which there is no difference, it is not possible that some of them can be perceived and that others cannot; the fourth, that there is no true perception proceeding from the senses, to which there is not some other perception opposed which in no respect differs from it, and which cannot be perceived. Now of these four principles, the second and third are admitted by every one. Epicurus does not admit the
