Does this mean that wisdom, madness and folly are all one, that there is no difference between them? Of course not, says Solomon. Wisdom makes a vast difference and transforms a man’s life on earth.
It has always been regarded as a form of torture to make a person do work and then to cancel all the results of that work, to force someone dig a hole and then force them to fill it in again. But if we do not know God, we are those get absolutely no profit from life at all. Why expend effort for something that produces no results? But what profit, he asks, hath a man of all his labour? The clearest point to measure this is at the end of life.
All that is under discussion here is earthly wisdom, for spiritual wisdom is something altogether higher and more profitable. It is a mistake to try to apply this passage to the subject of spiritual wisdom which is not in view here.