By the age of 16 he had already learned the Dutch language, essential to study Western medicine in Japan.

During his professional career, he was disappointed by the western medical system and became gradually convinced that traditional medicine (which often relied on prescribing a simple change of diet) was more effective.

He developed a theory that the secret to health and healing was to strengthen the body from within by a balanced dietary regime.

When he returned to civilian society, he opened a free clinic and began to practice exclusively using his own method.

With the support of leading figures (members of the Japanese imperial family, consuls, and other relationships acquired thanks to his high military rank) he quickly became successful.