Ecclesiastes 4:4; Ecclesiastes 4:7-8

4 Then I saw that all hard work and skillful effort come from rivalry. Even this is pointless. [It's like] trying to catch the wind.

7 Next, I turned to look at something pointless under the sun:

8 There are people who are all alone. They have no children or other family members. So there is no end to all the hard work they have to do. Their eyes are never satisfied with riches. But [they never ask themselves] why they are working so hard and depriving themselves of good things. Even this is pointless and a terrible tragedy.