In Zen monasteries students are often instructed to perform their chores in a state of complete alertness and presence, meaning their minds were completely empty of all thoughts as they worked. To test their students, the Zen Masters would sneak up behind the students and whack them over the head with a stick.
If the student was truly in a state of ‘no-thought presence’ then they would be so supremely alert that they would notice, either through their outer or inner senses, the Zen Master approaching and thereby avoid being whacked. But if a student was lost in their thoughts while they worked their alertness level would be far more subdued and information from their outer and inner senses would be drowned out by the noise of the thoughts in their head and they could easily be “snuck up upon.” They would invariably get whacked by the stick.
When in a state of ‘no-mind,’ one is in an intense state of presence and acute alertness. Once the level of conscious attention begins sinking then the mental noise begins and thoughts take over. We sink back into the endless thought patterns looping constantly through our mind. The state of stillness and presence is lost. It is then much easier to get whacked over the head.
When was the last time you got whacked over the head by a Zen stick?