Promoted to rear admiral in 1943, Takagi was regarded as the navy's leading intellectual. Navy Minister Shimada Shigetaro asked him to compile a report on the lessons to be learned from the war, but Takagi went beyond the assigned task and concluded that Japan had to make peace as quickly as possible and that the government headed by General Tojo Hideki would have to be replaced. Reluctant to show the report to Shimada, Takagi entered into an abortive plot to assassinate Tojo. He was transferred to the Research Department of the Naval War College, where he worked from 1944 to 1945, and with encouragement from the new minister of the navy, Yonai Mitsumasa, he prepared a top-secret report on the best way for Japan to withdraw from the war. Because of his efforts to remove Tojo from power and his realistic approach to ending the war, he has been highly regarded by Japanese naval historians. Takagi died on 27 June 1979. Hirama Yoichi
Evans, David C., and Mark R. Peattie. Kaigun: Strategy, Tactics, and Technology in the Imperial Japanese Navy, 1887–1941. Annapolis, MD: Naval Institute Press, 1997.; Takagi Sokichi. Takagi Sokichi Nitsuki (Dairy of Takagi Sokichi). Tokyo: Mainichi Shinbun, 1945.