These "four points of an itinerant salesman" are in fact the "washing kungfu" passed down by the wandering salesman of days past; others have called it "poison nerves."
陳朝陽口中的「江湖四點經」就是昔日江湖賣藝師父所傳授下來的「洗功門」術，也有人稱之為「毒神經」。