Aiki (martial arts principle) and its practice is often kept within a particular individual or two from a family/school lineage. Culturally, and due to certain necessities of the time period, the aiki knowledge was usually a very well guarded secret and rarely disclosed. The oldest book to have historically discuss aiki was the 1899 Budo Hiketsu-Aiki no Jutsu. On the subject of aiki it was written: The Textbook of Jujutsu (Jujutsu Kyoju-sho Ryu no Maki) from 1913 wrote: Aiki (martial arts principle) Aiki from a Japanese budo term, at its most basic is a principle that allows a conditioned practitioner to negate or redirect
Budo Senmon Gakko (Bujutsu Specialist School) in 1912, and then the Budo Senmon Gakko in 1919 when the term 'budo' officially replaced 'bujutsu'. The Budo Senmon Gakko (or Busen as it became known) together with the Tokyo Koto Shihan Gakko (Tokyo Higher Normal School) led the way in producing young instructors; these would be posted to schools throughout the country, to teach children the arts. The first class of 8 students graduated in March 1914. Budo Senmon Gakko continued to produce excellent instructors until the outbreak of World War II, as more and more students were drafted into the Japanese military. After the