Ecclesiastes 2:19-21

¹⁹And who knoweth whether he shall be a wise man or a fool? yet shall he have rule over all my labour wherein I have laboured, and wherein I have shewed myself wise under the sun. This is also vanity.

²⁰Therefore I went about to cause my heart to despair of all the labour which I took under the sun.

²¹For there is a man whose labour is in wisdom, and in knowledge, and in equity; yet to a man that hath not laboured therein shall he leave it for his portion. This also is vanity and a great evil.