Solomon
Ecclesiastes 1:13ESV·traditional attribution

And I applied my heart to seek and to search out by wisdom all that is done under heaven. It is an unhappy business that God has given to the children of man to be busy with.

Matthew Henry Presbyterian @wholebiblehenry

Solomon, having asserted in general that all is vanity, and having given some general proofs of it, now takes the most effectual method to evince the truth of it, 1. By his own experience; he tried them all, and found them vanity. 2.

Commenting on Ecclesiastes 1:12-18

Jamieson-Fausset-Brown Reformed @jfbcommentary

this sore travail--namely, that of "searching out all things done under heaven." Not human wisdom in general, which comes afterwards (Ecc 2:12, &c.), but laborious enquiries into, and speculations about, the works of men; for example, political science. As man is doomed to get his bread, so his knowledge, by the sweat of his brow (Gen 3:19) [GILL]. exercised--that is, disciplined; literally, "that they may thereby chastise, or humble themselves."

Geneva Bible Notes Reformed @genevanotes

And I gave my heart to seek and search out by wisdom concerning all [things] that are done under heaven: this grievous labour hath God given to the sons of man to be exercised with it. (i) Man by nature has a desire to know, and yet is not able to come to the perfection of knowledge, which is the punishment of sin, to humble...