Ecclesiastes to Proverbs
Solomon's proverbs.
Proverbs
Near the end of the book, Ecclesiastes says Solomon sought and composed many proverbs.
Those proverbs that Solomon wrote and collected become the book of Proverbs. Most of the proverbs in the book of Proverbs were written by Solomon, but some were collected from other composers. For example, later in time, the friends of King Hezekiah wrote some proverbs that were included in the book of Proverbs.
Fear of Yahvah
After 12 chapters of experimentation and vanity Solomon offers a conclusion at the end of Ecclesiastes. He says the fear of God is what's important. Fear of God is where Proverbs begins.
The way Proverbs states that fearing God is the beginning of wisdom means nothing Solomon did in Ecclesiastes prior to reaching his conclusion was actually borne of wisdom. He did want he wanted, ignoring God, and contemplated the experience after the fact.
The lesson for the observant reader is that you do not have to try all the stuff Solomon did to find contentment. His conclusion is where you should begin. The real journey begins by fearing God.
So Ecclesiastes gets it coming and going. Job shows a better way than Ecclesiastes and Proverbs says wisdom begins where Ecclesiastes ends.