When SEN no Sotan died in 1658, Sohen inherited the traditional art of tea ceremony from Sotan and became the fourth heir of the pseudonym Fushin-an; incidentally, the pseudonym has been used frequently by Omotesenke (the family of Omotesen) and the first Fushin-an was SEN no Rikyu.
万治元年（1658年）に千宗旦が死ぬと茶統をついで不審庵四世となる（一世は千利休）（表千家がよく用いる）。