Prominent Japanese economist, specialist in colonial politics, a professor of Imperial Tokyo University, Yanaihara Tadao (1893-1961) was one of a few people who dared to oppose the aggressive policy of Japanese government before and during the Second World War. He developed his own view of patriotism and nationalism, regarding as a true patriot a person who wished for the moral development of his or her country and fought the injustice. In the years leading up to the war he stated the necessity of pacifism, calling every war evil in the ultimate, divine sense, developing at the same time the concept of the «just war» ( gisenron ), which can be considered good seen from the point of view of this, imperfect life. Yanaihara’s theory of pacifism is, on one hand, the continuation of the one proposed by his spiritual teacher, the founder of the Non-Church movement, Uchimura Kanzo (1861-1930); one the other hand, being a person of different historical period, directly witnessing the boundless spread of Japanese militarism and enormous hardships brought by the war, Yanaihara introduced a number of corrections to the idealistic theory of his teacher and proposed quite a specific explanation of the international situation and the state of affairs in Japan. Yanaihara’s philosophical concepts influenced greatly both his contemporaries and successors of the pacifist ideas in postwar Japan, and contributed to the discussion about interrelations of pacifism and patriotism, and also patriotism and religion.