Kakua's One Note
Kakua was the first Japanese to study Zen in China. He received the true teachings and meditated constantly in the mountains. When asked to teach, he would always say a few words and then move on.
When he returned to Japan, the emperor invited him to give a teaching at the palace.
Kakua stood silent. He took out his flute and blew one short note. He then bowed politely, left the palace, and was never seen again.
Because Kakua showed nothing except for that one note, he is not remembered for having brought Zen into Japan.