Ecclesiastes Chapter 2 Verses 11-12

Ecc 2:11 Thus I considered all my activities which my hands had done and the labor which I had exerted, and behold all was vanity and striving after wind and there was no profit under the sun. Ecc 2:12 So I turned to consider wisdom, madness and folly; for what will the man do who will come after the king except what has already been done?