|Prayer flags in the wind, Nepal|
Photo: Stefanie Buehler
The argument is based on interpreting what one sees with the mind, rather than simply having direct experience in the moment. As such, there is no right-mindedness while the monks argue about what is happening. They are removed from the moment. This is what is meant by "it is your mind that moves."
The argument is one of delusion since it is the debating of interpretations of reality - what each monk thinks about what they see - rather than reality itself. The distancing from reality is actually three-fold. First, there is the interpretation of reality. Second, there is the evaluation of the other monk's interpretation. Then third, there is the comparison of the evaluations against one another. Once we let our minds "move", we are quickly swept out of the moment and away from the moment into an intellectual hall of mirrors that is merely delusion.
The Sixth Patriarch was chastising the monks for their lack of discipline.