In the late 1950s and early 1960s, Pirsig taught rhetoric at Montana State College – Bozeman and, with the encouragement of an older colleague, Sarah Vinke, decided to explore what exactly was meant by the term "quality". He assigned his students the task of defining the word. This, coupled with a Native American Church peyote ceremony he attended with an anthropologist friend, James Verne Dusenberry, led Pirsig into what he called "a mushroom cloud of thought." Pirsig began developing his ideas about quality in his first book, "Zen and the Art of Motorcycle Maintenance", and expanded and codified his ideas into the MOQ in "Lila".