After ten years of apprenticeship, Tenno achieved the rank of Zen teacher. One rainy day, he went to visit the famous master Nan-in. When he walked in, the master greeted him with a question, "Did you leave your wooden clogs and umbrella on the porch?"
"Yes," Tenno replied.
"Tell me," the master continued, "did you place your umbrella to the left of your shoes, or to the right?"
Tenno did not know the answer, and realized that he had not yet attained full awareness. So he became Nan-in's apprentice and studied under him for ten more years.