Rishi is a Sanskrit word which refers to the person who constantly leads a straightforward life. The Tibetan word for "rishi" is trangsong, which means "direct" and "upright." So this term refers to someone who leads a direct and upright life by not introducing new complications into their life situation. This is a permanent discipline, the ultimate discipline. We simplify life rather than getting involved with new gadgets or finding new concoctions with which to mix our life.
Condensed from "The Eightfold Path," in The Myth of Freedom and the Way of Meditation, page 122 in the Shambhala Library edition.