While I was washing Hang Hang in the bath tub, he used his hand trying to slash the water. He asked "Why can't you break the water?" What a Dao-ish question? How inquisitive this young mind to raise this intriguing question about our physical world? Why can't you break the water?
"Well because it is not solid" I said. "You can only break things that are solid". We went on to enumerate solid things that can be broken. That's the best I can answer. Still let's keep these great questions coming!