His criticisms of governments and their war policies caused him to end up in prison on various occasions.

Due to his mother's illness and his father's early death he was moved that same year with his nurse to live with his grandparents in the Ishikawa Prefecture on the western side of the country.

In September 1905 he returned to Tokyo where he grew up with his mother in the city's Kanda quarter (today part of Chiyoda).

He was interested in the works of Nishida Kitaro, and Tanabe Hajime, neo-Kantianism, and then Marxism.

Tosaka died in Nagano Prison before the end of World War II.