An enigmatic figure, Nakagawa had a major impact on Zen as it was practiced in the 20th century, both in Japan and abroad.
Rather than carry on the samurai tradition of his father[dubious – discuss], Soen pondered a more spiritual occupation.
Koun recalled one occasion when Soen talked about how he was sitting zazen atop a platform on the balancing bars in the playground resulting in a "natural self-realization".
At the school library, Soen read a passage on impermanence and deluded approaches towards happiness by Schopenhauer, which provided him with a sense of clarity.
He enjoyed campus life, where he frequented the theater to hear renditions of classical masters and had a band of friends immersed within the artistic community of Japan.
A short while after graduation Soen attended a Dharma talk by Rinzai Zen master Keigaku Katsube at Shorin-ji and knew he wanted to become a monk.
Just like Bassui, Soen began travelling to Dai Bosatsu Mountain in Kai province (near Mount Fuji) doing solitary retreats as a hermit and then returning to the monastery to resume his duties as a monk.
On the mountain Soen sat zazen and wrote haikus, bathing in nearby streams and living off of the land.
One day while on the mountain he nearly killed himself by eating poisonous mushrooms, and some peasants from nearby took him in and nursed him back to health.
In 1935 Nakagawa accompanied Katsube Roshi to lead a weekend retreat for Tokyo Imperial University students, and realized he forgot the kyosaku (Zen stick).
[2]This remark struck a deep and spontaneous chord within Soen, and so he requested dokusan with Gempo following the talk where he expressed the desire to train under him.
In 1937 Nakagawa makes a trip with Gempo Yamamoto to Xinjing in Japanese-occupied Northeast China, to start a branch of Myoshin-ji Zen with the aim of moralizing the slave labor force used in Nissan-owned mining enterprises.
Here, Soen mentioned to Yamada his earlier dream of one day founding a non-traditional monastery on Dai Bosatsu Mountain in the spirit of Bassui.
He found Senzaki's approach to Zen refreshing, and was happy to find a new freedom in expressing himself to followers that would be unheard of in Japan.
Free to combine his love for Japanese theater (Noh) into analogies that paralleled sayings of the great Zen masters of the past.
Over the next few years Soen set out to visit other masters stating that, since he had only finished 500 koans of Hakuin's 1700 curriculum, he needed more training.
In 1963, Nakagawa traveled to the United States, India, Israel, Egypt, England, Austria and Denmark with Charles Gooding, a former student of Nyogen Senzaki, teaching Zen with various sanghas.
In 1969, Nakagawa travelled again to Israel, England, Egypt], New york, California and Hawaii to lead sesshins with sanghas.
In 1971, Nakagawa made his 9th visit to the US, helping The Zen Studies Society (founded by Cornelius Crane) purchase land in the Catskill Mountains for International Dai Bosatsu Zendo.
In 1972, Nakagawa made his 10th visit to the United States where he gave Dharma transmission to Eido Tai Shimano.