As far as human senses go, the passerby from a few hours ago left nothing behind but footprints. But to a dog’s sense of smell, a scent remains that humans aren’t aware of. In terms of ordinary people’s senses, the good or bad things done a few days ago left no mark except for the memory of them. But in the eyes of sublime beings, virtuous or non-virtuous karma has made its mark. Ordinary people, however, are not aware of it.