One possible version:

     Maybe no one would regard himself as foolish. But please look at what the man is doing in the picture:

He is cutting down an old tree just to get the ball on the tree for his children. If so, how can we admit that

he is wise?

     Just as somebody abandons a watermelon but wants a piece of sesame, there are many phenomena

which we can't understand in society.

     For example, a person who strives for power and wealth at all costs would rather lose his happiness,

friendship and even his conscience. Factories strive for profits at the cost of polluting the environment.

Wars between countries ignore people's lives. All these phenomena are really blind to reason, but they all

can be called one name-strive for little profit at a dear cost. 

     Therefore, when we are going to do something, we should calculate the cost and find the most wise 

method.