When you are completely focused, say if you are snowboarding down a mountain so fast and steep that if you think, you will stumble and get seriously injured, you are in the flow of the moment.  The modern term from psychology is “flow state”, but mystical teachings from Indian Yoga and other traditions have described merging completely with an activity to accomplish it perfectly and see it in it’s true state: we also refer to an experience like this as going beyond duality. By that we mean that there is no separation between you and the activity that you are performing, or anything else in life for that matter. This is something you experience when you go beyond thought and the constant dialog in your mind stops.