Completely agree. I'd like to also recommend another book in the spirit of Ecclesiastes: Tolstoy's Confession. A Confession was published shortly after Anna Karenina and at a time when Tolstoy (in his fifties) was widely considered to be one of the world's preeminent writers. He had vast wealth, fame, and a large family. Nevertheless, he was so overwhelmed by the vanity of existence that he was convinced suicide was the bravest, most reasonable course of action.

Apart from pure cowardice, he writes that what stopped him from taking his life was a vague intuition that his own logical reasoning about life's purpose was sound but somehow incomplete. His eventual insight is as follows: life is not meaningless because logically it must be so. Logic cannot 'negate' life because it is itself a byproduct of life. If one reduces life to a form conducive to logic, one reduces it to a cold, dead simulacra that may indeed not be worth living. Instead, Tolstoy argues, the life that is worth living, and the one that so many of the peasants around him lived, was one guided by (potentially unconscious) faith. He concludes that this faith in the transcendent must be the source of life ("God is life") and that life is a logically impossibility save for this faith.

His post-Confession writings are all dedicated to his interpretation of the Christian scriptures. I'll also note that his advocacy and envagelism of Christian pacifism was a direct influence on Gandhi and MLK Jr.

[1] https://en.wikipedia.org/wiki/A_Confession [2] http://www.arvindguptatoys.com/arvindgupta/confessions-tolst...