Once upon a time, there was a Chinese farmer whose horse ran away all the neighbours came around to commiserate in that evening "so sorry that your horse ran away,that's too bad"and he said "may be".
The next day, the horse came back bringing seven wild horses with it and everybody came around in the evening and said oh!isn't that lucky,what a great turn of events you've now got eight horses and he said "may be".
The next day, his son tried to break one of these horses and ride it and was thrown and broke his leg and they all said oh that's too bad and he said "may be".
The following day, the conscription officers came around to recruit to force people into the army and they rejected his son because he had broken leg and all the people came around and said that isn't great.And he said "may be"
That's an attitude of not thinking of things in terms of gain or loss, advantage or disadvantage.There isn't any fixed good or bad and so his point of view is what is called "non choosing"and keep his mind in non choosing state of mind.
It is a grate lesson to learn and practise from this story.