Water and ice

One day in winter, the Teacher and the student were walking along the river bank.
- Teacher! People do not understand each other. People try to communicate, read books that tell about mutual understanding - and stumble on an invisible wall. Why is that? Can't you teach it?
- Come with me - Teacher went across the ice to the middle of the river. - Look down. Do you see something here?
- Not. How can I see something through the ice?
“There, under the ice, is a whole world unknown to you.” Melt the ice - and it will become the water that gives life to the whole world. But pour the prepared water here - it will freeze and only strengthen the ice kingdom.