Ecclesiastes 2:18-21

Yea, I hated all my labour which I had taken under the sun: because I should leave it unto the man that shall be after me. And 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. Therefore I went about to cause my heart to despair of all the labour which I took under the sun. For 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.