12 Then I turned myself to consider wisdom and madness and folly; for what can the man do who succeeds the king?—only what he has already done.
13 Then I saw that wisdom excels folly as light excels darkness.
14 The wise man’s eyes are in his head, but the fool walks in darkness.
Yet I myself perceived that the same event happens to them all.
15 So I said in my heart, “As it happens to the fool, it also happens to me, and why was I then more wise?” Then I said in my heart, “This also is vanity.”
16 For there is no more remembrance of the wise than of the fool forever, since all that now is will be forgotten in the days to come. and how does a wise man die? As the fool!
17 Therefore I hated life because the work that was done under the sun was distressing to me, for all is vanity and grasping for the wind.
I turned (v.12) — Implies a deeper study
The question (v.12) “what can the man do” etc. means no one could, or can, possibly compete with King Solomon in determining the vanity of things under the sun, for no one ever was, or will be, as efficiently equipped as he was for this experiment. — Williams, page 440.
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Verse 12b is saying that if a man comes after Solomon and decides to do the same study of wisdom and folly, what can that man do except what Solomon has already done? (And he would come to the same conclusion.) — Grace, page 1169.
darkness (v.14) — symbolizing evil and foolishness
It is certain that wisdom is relatively superior to folly; for the wise man makes a better job of life than the fool. But this relative is cancelled out by the absolute of death, a fact which seriously challenges the worth of wisdom. There is a paradox about wisdom; wisdom means looking forward. While the fool, like the grasshopper, lives for the moment, the wise man, like the ant, dips into the future; he takes his bearings from tomorrow, and endeavors to plot his course accordingly (v.14). Yet this wisdom is most hazardous; for it is not in our power to foresee, still less to control, the future. — Guthrie, page 572.
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