Proverbs 15:14 in the World English Bible
The heart of one who has understanding seeks knowledge, but the mouths of fools feed on folly.
Context
13 A merry heart maketh a cheerful countenance: but by sorrow of the heart the spirit is broken.
14 The heart of him that hath understanding seeketh knowledge: but the mouth of fools feedeth on foolishness.
15 All the days of the afflicted are evil: but he that is of a merry heart hath a continual feast.