13. And I gave my heart to seek and search out by wisdom concerning all things that are done under heaven: this grievous labor hath God given to the sons of man to be exercised with it.
14. I have seen all the works that are done under the sun; and behold, all is vanity and vexation of spirit.
15. That which is crooked cannot be made straight: and that which is wanting cannot be numbered.
16. I communed with my own heart, saying, Lo, I have come to great estate, and have gained more wisdom than all they that have been before me in Jerusalem: and my heart had great experience of wisdom and knowledge.
17. And I gave my heart to know wisdom, and to know madness and folly: I perceived that this also is vexation of spirit.
18. For in much wisdom is much grief: and he that increaseth knowledge increaseth sorrow.