Ecclesiastes 2:12

And I turned myself to behold wisdom, and madness, and folly: for what can the man do that cometh after the king? even that which hath been already done.

Ecclesiastes 1:17

And I gave my heart to know wisdom, and to know madness and folly: I perceived that this also is vexation of spirit.

Ecclesiastes 7:25

I applied my heart to know, and to search, and to seek out wisdom, and the reason of things, and to know the wickedness of folly, even of foolishness and madness:

Ecclesiastes 1:9-10

The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun.

Treasury of Scripture Knowledge

Summary

And I turned myself to behold wisdom, and madness, and folly: for what can the man do that cometh after the king? even that which hath been already done.

Even that which hath been already done

Bible References

I turned

Ecclesiastes 1:17
And I gave my heart to know wisdom, and to know madness and folly: I perceived that this also is vexation of spirit.
Ecclesiastes 7:25
I applied my heart to know, and to search, and to seek out wisdom, and the reason of things, and to know the wickedness of folly, even of foolishness and madness:

Even that which hath been already done

Ecclesiastes 2:25
For who can eat, or who else can hasten to it more than I?