Why does it say "Ra'isi"?
Rid: After I turned to understand their essence, I knew clearly.
Metzudas David: I saw intellectually, that even though one should despise folly, it has a purpose.
Why is there a Patach under the Lamed in "la'Chachmah"?
Rashbam: It is the known Chachmah - that we are used to, which is needed for the world. It is not deep. If there were a Sheva under the Lamed, it would refer to deep, great Chachmah.
Verse 12 mentioned "Holelos v'Sichlus" Why does our verse mention only Sichlus?
Rashi: Here it refers to evil. (Rashi 12 - verse 12 refers to the punishment for Aveiros.)
What is the comparison to the advantage of light over darkness?
Ibn Ezra: Light [enables one to] divide forms, to see what is close and far, and understand everything's status. So is the way of Chachmah!
Ri Kara: Chachmah teaches man the path in which he will not stumble, like one who walks in daylight. A fool, who does not consider a matter before doing it, is like one who goes in darkness.
Seforno: Chachmah is what is understood with the power of intellect. Sichlus senses the tangible without any contemplation, just like darkness is a total lack of light.
Metzudas David: Something is known only due to its opposite. If not for folly, the glory of Chachmah would not be known, just like the good of light is known only due to darkness.
Ma'alos ha'Torah (DH u'Mah sheha'Dalet): The primary learning is at night. When folly is reversed to Chachmah, its attribute is known, like the advantage of light over dark. At night, Kelipos (shells of Tum'ah) rule. Via , Torah which is called light, he breaks the power of the Kelipos, and the advantage of Chachmah is seen.
