Man’s work never satisfies

Ecclesiastes 1:8

All things are full of labour; man cannot utter it: the eye is not satisfied with seeing, nor the ear filled with hearing.

Madness and folly

Ecclesiastes 1:15-18

That which is crooked cannot be made straight: and that which is wanting cannot be numbered.   I communed with mine own heart, saying, Lo, I am come to great estate, and have gotten more wisdom than all they that have been before me in Jerusalem: yea, my heart had great experience of wisdom and knowledge.  

And I gave my heart to know wisdom, and to know madness and folly: I perceived that this also is vexation of spirit.   For in much wisdom is much grief: and he that increaseth knowledge increaseth sorrow.

Vanity: Personal Pleasures

Ecclesiastes 2:1-5

I said in mine heart, Go to now, I will prove thee with mirth, therefore enjoy pleasure: and, behold, this also is vanity.   I said of laughter, It is mad: and of mirth, What doeth it?  

I sought in mine heart to give myself unto wine, yet acquainting mine heart with wisdom; and to lay hold on folly, till I might see what was that good for the sons of men, which they should do under the heaven all the days of their life.   I made me great works; I builded me houses; I planted me vineyards:   I made me gardens and orchards, and I planted trees in them of all kind of fruits:

Vanity: Riches and Glory

Ecclesiastes 2:7-9

I got me servants and maidens, and had servants born in my house; also I had great possessions of great and small cattle above all that were in Jerusalem before me:   I gathered me also silver and gold, and the peculiar treasure of kings and of the provinces: I gat me men singers and women singers, and the delights of the sons of men, as musical instruments, and that of all sorts.  

So I was great, and increased more than all that were before me in Jerusalem: also my wisdom remained with me.