Even though you try very hard, the progress you make is always little by little. It is not like going out in a shower in which you know when you get wet. In a fog, you do not know you are getting wet, but as you keep walking you get wet little by little. If your mind has ideas of progress, you may say, 'Oh, this pace is terrible!' But actually it is not. When you get wet in a fog it is very difficult to dry yourself.