One of his first instructors was the blind master named Po (Keye Luke). Po considered Caine his favorite pupil and behaved more like an elderly grandfather. Caine was given the nickname "Grasshopper" by Master Po; the reference was from an exchange where the still ignorant young Caine asked the old blind master how he could function without seeing. Po asked Caine to close his eyes and describe what he could hear. Caine explained that he could hear the water flowing in a nearby fountain and birds in a nearby cage. Po then asked if Caine could hear his own heartbeat or the grasshopper at his feet (Caine hadn't noticed the insect until that moment). Incredulous, Caine asked Po, "Old man – how is it that you hear these things?" Po's reply was, "Young man, how is it that you do not?" From that point on, Po affectionately called Caine "Grasshopper".