Ecclesiastes Chapter 2 Verses 11 and 12

Ecc 2:11 Then I considered all that my hands had done and the toil I had expended in doing it, and behold, all was vanity and a striving after wind, and there was nothing to be gained under the sun.Ecc 2:12 So I turned to consider wisdom and madness and folly. For what can the man do who comes after the king? Only what has already been done.