And who knoweth whether he shall be a wise man or a fool? yet shall he have rule over all my labour wherein I have laboured, and wherein I have shewed myself wise under the sun. This is also vanity.

For what hath man of all his labour, and of the vexation of his heart, wherein he hath laboured under the sun?

What profit hath he that worketh in that wherein he laboureth?

All this have I seen, and applied my heart unto every work that is done under the sun: there is a time wherein one man ruleth over another to his own hurt.

If the iron be blunt, and he do not whet the edge, then must he put to more strength: but wisdom is profitable to direct.