When I was having a walk in the community park, I saw a little boy who was playing soap bubbles. He blew one after another into the sky; they looked colorful under the sunlight. He became very excited when he made a big bubble, and tried to keep it in his palms. But at the moment he touched it, it burst out into nowhere. He felt quite frustrated, but he decided to try again. He was more careful when he tried to take the bubble, but he failed to keep it again. He couldn't bear this time and began to cry.
The little boy had no chance to keep the bubble, because the bubble can't keep itself. It is going to burst out since the moment of being blown up. It is just the temporary state of existing of the soap water, the air inside and outside, the temperature, the wind…and all of them consists in something else.
When we look around our world with insight, we can understand why Buddha said: “all phenomena are like dreams and bubbles, also like dew and lightening”. Not to say the bubble can't keep itself, the body can't keep itself, the plant can't keep itself, the climate can't keep itself, the sun or earth can't keep itself…every state of existing depends on other conditions. Nothing depends on itself!
A bubble is just a bubble, it is not an independent self, and it is a dependent arising appearance. The same for anything else in this world. The joy can't keep itself, the sorrow can't keep itself, the happiness can't keep itself, the suffering can't keep itself…any state of form is possible to be changed. Nothing can be fixed in itself!
The bubble is showing us an “empty self”, don't ignore it. Everything is manifesting with an “empty self”, keep alert.