"Oh! I know!" cried Euergetes. "You keep Greek slaves, who must even read and write for you. Pray is there a market where I may purchase men, who, after a night of carousing, will bear our headache for us? By the shores of the Tiber you love many things better than learning." "And thereby," added Aristarchus, "deprive yourselves of the noblest and subtlest of pleasures, for the purest enjoyment is ever that which we earn at the cost of some pains and effort." "But all that you earn by this kind of labor," returned Publius, "is petty and unimportant. It puts me in mind of a man who removes a block of stone in the sweat of his brow only to lay it on a sparrow's feather in order that it may not be carried away by the wind." "And what is great--and what is small?" asked Aristarchus. "Very opposite opinions on that subject may be equally true, since it depends solely on us and our feelings how things appear to us--whether cold or warm; lovely or repulsive--and when Protagoras says that 'man is the measure of all things,' that is the most acceptable of all the maxims of the Sophists; moreover the smallest matter--as you will fully appreciate --acquires an importance all the greater in proportion as the thing is perfect, of which it forms a part. If you slit the ear of a cart-horse, what does it signify? but suppose the same thing were to happen to a thoroughbred horse, a charger that you ride on to battle! "A wrinkle or a tooth more or less in the face of a peasant woman matters little, or not at all, but it is quite different in a celebrated beauty. If you scrawl all over the face with which the coarse finger of the potter has decorated a water-jar, the injury to the wretched pot is but small, but if you scratch, only with a needle's point, that gem with the portraits of Ptolemy and Arsinoe, which clasps Cleopatra's robe round her fair throat, the richest queen will grieve as though she had suffered some serious loss. "Now, what is there more perfect or more worthy to be treasured than the noblest works of great thinkers and great poets. "To preserve them from injury, to purge them from the errors which, in the course of time, may have spotted their immaculate purity, this is our task; and if we do indeed raise blocks of stone it is not to weight a sparrow's feather that it may not be blown away, but to seal the door which guards a precious possession, and to preserve a gem from injury.