Ecclesiastes 10:1-3

World English Bible

10 Dead flies cause the oil of the perfumer to produce an evil odor;
    so does a little folly outweigh wisdom and honor.
² A wise man’s heart is at his right hand,
but a fool’s heart at his left. ³     Yes also when the fool walks by the way, his understanding fails him, and he says to everyone that he is a fool.