Ecclesiastes 2:14

I have seen everything that is done under the sun;and behold, all is vanity and a striving after wind.

2:17

And I applied my mind to wisdom and to know madness and folly, and I perceived that this also is but a striving after wind.
For in wisdom there is much vexation, and he who increases knowledge increases sorrow.

2:15

Then I said to myself “what befalls the fool will befall me also; why for most  I been so very wise?”. And I said to myself this also is vanity.  For of the wise man as of the fool there is no enduring remembrance, seeing the days to come all will have been long forgotten. How the wise man dies just like the fool! So I hated life, because what is done under the sun is grievous to me; for all is vanity and a striving after wind.