In June 1910, Soseki was hospitalized at the Nagayo Gastrointestinal Hospital for gastric ulcer, while writing 'Mon,' which was the third novel of the trilogy in his early period following "Sanshiro" and "Sorekara."
明治43年（1910年）6月、『三四郎』『それから』に続く前期3部作の3作目にあたる「門(小説)」を執筆途中に胃潰瘍で長与胃腸病院（長與胃腸病院）に入院。