Ecclesiastes 10:2
"A wise man’s heart is at his right hand; but a fool’s heart at his left."
Cross References (ranked by relevance)
A fool also is full of words: a man cannot tell what shall be; and what shall be after him, who can tell him?
Wherefore is there a price in the hand of a fool to get wisdom, seeing he hath no heart to it?
If the iron be blunt, and he do not whet the edge, then must he put to more strength: but wisdom is profitable to direct.
The wisdom of the prudent is to understand his way: but the folly of fools is deceit.
Whatsoever thy hand findeth to do, do it with thy might; for there is no work, nor device, nor knowledge, nor wisdom, in the grave, whither thou goest.