31. To these we may add thousands of the most frivolous practices, that are to be observed if any part of the body should jump, or if, when friends are walking arm-in-arm, a stone, or a dog, or a boy, should come between them. And the kicking of a stone, as if it were a divider of friends, does less harm than to cuff an innocent boy if he happens to run between men who are walking side by side. But it is delightful that the boys are sometimes avenged by the dogs; for frequently men are so superstitious as to venture upon striking a dog who has run between them, -- not with impunity however, for instead of a superstitious remedy, the dog sometimes makes his assailant run in hot haste for a real surgeon. To this class, too, belong the following rules: To tread upon the threshold when you go out in front of the house; to go back to bed if any one should sneeze when you are putting on your slippers; to return home if you stumble when going to a place; when your clothes are eaten by mice, to be more frightened at the prospect of coming misfortune than grieved by your present loss. Whence that witty saying of Cato, who, when consulted by a man who told him that the mice had eaten his boots, replied, "That is not strange, but it would have been very strange indeed if the boots had eaten the mice."