9Whoso removeth stones shall be hurt therewith; and he that cleaveth wood shall be endangered thereby. 10If the iron be blunt, and he do not whet the edge, then must he put to more strength: but wisdom is profitable to direct. 11Surely the serpent will bite without enchantment; and a babbler is no better. 12The words of a wise man's mouth are gracious; but the lips of a fool will swallow up himself.13The beginning of the words of his mouth is foolishness: and the end of his talk is mischievous madness. 14A fool also is full of words: a man cannot tell what shall be; and what shall be after him, who can tell him? 15The labour of the foolish wearieth every one of them, because he knoweth not how to go to the city.