A disciple and a master were going on a pilgrimage in northern India. Tired, they sat on a big rock under a tree. After a while disciple asked the master, “Dear Sir, this rock is so hard and strong. What could be stronger than this rock?”
“Iron, my son. Iron can cut the rocks and hence is stronger than the rock.”
“Hmm.... what could be stronger than iron, Sir?”
“Well, fire can melt the iron. So, you can consider fire to be more potent than the iron.”
“You are right. Is there anything more potent than the fire.”
“You can say that water can pacify the fire, so water can be considered as more powerful than the fire.”
The disciple thought for a moment and then said, “In that case, wind can even lift the water to the clouds. So air should be considered as more powerful than the water.”