16. I--I spake with my heart, saying, `I, lo, I have magnified and added wisdom above every one who hath been before me at Jerusalem, and my heart hath seen abundantly wisdom and knowledge.
17. And I give my heart to know wisdom, and to know madness and folly: I have known that even this [is] vexation of spirit;
18. for, in abundance of wisdom [is] abundance of sadness, and he who addeth knowledge addeth pain.'