After filling an empty water bottle with stones, a professor took out a box of pebbles and poured them into the water bottle. He gently shook the water bottle so that the pebbles could roll into the space between the stones. Then the professor took out a box of sand and poured it into the cup. He shook the water bottle so that the sand filled all the gaps. Finally, he poured water into the water bottle until the water penetrated the sand. The child overflows the rim of the water bottle. After that, the professor said to the students, "Now, I want you to understand this water bottle as life.
The stones inside represent the most important things in life, such as family, partner, health and children, all of which are very important to us. Once lost, they will never be repaired; the pebbles represent the more important things in life, such as work, house and car; the sand represents the daily trifles of life; Water represents worry and melancholy. If we put water and sand in the water bottle first, there would be no room for stones and pebbles.