I am just an enthusiast of this art. Still in the end I understand some philosophies can be applied to multiple arts.
勇 yū can be applied to surfing because catching waves in the ominous ocean takes courage. Braveness is the core of the extreme sports industry. Hiding like a turtle in a shell is not living at all. A true warrior must have heroic courage. It is absolutely risky. It is living life completely, fully and wonderfully. Heroic courage is not blind. It is intelligent and strong.
According to Histoire Ecclesiastique Des Isles Et Royaumes Du Japon, written by François Solier of the Society of Jesus in 1627, Yasuke was likely from Portuguese Mozambique. Solier’s account may however have been an assumption as it was written so long after the event and there is no surviving contemporary account that corroborates it. Therefore, although there is no evidence, it is also possible that he also came from Portugal, Portuguese Angola or Ethiopia, and he could conceivably originally have been an African mercenary in the employ of an Indian sovereign, of which there were many at this time.
A 2013 investigation by the light entertainment television program Discovery of the World’s Mysteries (世界ふしぎ発見) suggested that Yasuke was a Makua named Yasufe. This was not a highly journalistic investigation, and the program provided little proof for their conclusions and the Makua didn’t have any significant conflict with the Portuguese based on the Island of Mozambique until 1585  He may have been a member of the Yao people, who were just coming into contact with the Portuguese at the time, which might account for his name, Yao added to the common Japanese male name suffix of suke.
Yasuke arrived in Japan in 1579 in the service of the Italian Jesuit Alessandro Valignano, who had been appointed the Visitor (inspector) of the Jesuit missions in the Indies, meaning East Africa, South and East Asia. He accompanied Valignano when the latter came to the capital area in March 1581 and caused something of a sensation. In one event, several people were crushed to death while clamouring to get a look at him, the Jesuits feared their church would be flattened but they managed to avert disaster. Nobunaga heard the noise from the temple where he was staying and expressed a desire to see him. Suspecting the black color of his skin to be black ink, Nobunaga had him strip from the waist up and made him scrub his skin.These events are recorded in a 1581 letter of the Jesuit Luís Fróis to Lourenço Mexia and in the 1582 Annual Report of the Jesuit Mission in Japan, also by Fróis. These were published in Cartas que os padres e irmãos da Companhia de Jesus escreverão dos reynos de Japão e China II, normally known simply as Cartas, in 1598. Satisfied that he was in fact black, Nobunaga seems to have taken a shine to him, and at some point, although when is not clear, he was either given (Japanese accounts indicate him presented to Nobunaga, although European accounts do not mention this) or allowed to enter Nobunaga’s service.
The Lord Nobunaga Chronicle (信長公記 Shinchō Kōki) corroborates Fróis’ account, and describes their meeting thus: “On the 23rd of the 2nd month [March 23, 1581], a black page (黒坊主 kuro-bōzu) came from the Christian countries. The man was healthy and good-looking with a good demeanour. Moreover, Nobunaga praised Yasuke’s strength, describing it as that of ten normal men. Nobunaga’s nephew, probably Tsuda Nobusumi, gave him a sum of money at this first meeting.
In May, Yasuke went with Nobunaga to his castle at Azuchi and popular rumors said he might be ennobled. The diarist Matsudaira Ietada, described him as 6 shaku 2 sun (6 ft. 2 in., or 188 cm.). He was black, and his skin was like charcoal.” If so, his tall stature would have been very imposing to the Japanese of the time, even to a tall man like Nobunaga. Matsudaira stated that he was named Yasuke.