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Sôchin (壯鎭) - "Strength [and] Calm" ("Strongly Rooted") -"Сила [и] спокойствие" ("Прочно укорениться").
Sôchin was probably created by Funakoshi Yoshitaka in the late 1930s. There are number of similarities to Sôchin of Aragaki Seisho (an Okinawan martial arts master, 1840-1918(?1920)). Thus, Aragaki Sôchin could be used as a basis.
Aragaki Seisho (an Okinawan martial arts master, 1840-1918(?1920)) taught Sôchin to Mabuni Kenwa (1889-1952, the founder of Shitô ryû). As in case with Nijû Shi Ho (Niseishi), Sôchin could be learned by Funakoshi Yoshitaka and Nakayama Masatoshi from Mabuni Kenwa.
Funakoshi Gichin Sensei tried to rename Sôchin as Hakko ("Eight Storms" ("Восемь бурь")), but the new name didn't stay.
Tora Jo dôjô: Some notes on Sôchin
Nakayama Masatoshi "Best Karate. Vol. 10. Unsu, Sôchin, Nijû Shi Ho". Kodansha International, 1987.
Hirokazu Kanazawa "Shotokan Karate International Kata (Vol. 1)"
Fiore Tartaglia "Shôtôkan-Kata ab dem Schwarzgurt"
THE SHOTOKAN WAY – The Online Shotokan Karate Magazine: Sochin
Sôchin performed by Shirai Hiroshi Sensei in the JKA kata film (1960)
Osaka Yoshiharu Sensei - Sôchin