This article builds on the ethics of Watsuji Tetsurô (1889–1960) through a comparison with Mori Akira’s (1915–1976) the philosophy of education to show how Watsuji’s “ethics of emptiness” can be concretely manifested in human formation. While keeping Watsuji’s ethics in view, this article examines Mori Akira’s early philosophy of moral education in the 1950s, which can be found in his philosophy book, his teacher’s manual, and his moral education student textbooks. This article begins with Watsuji’s idea of “human existence” and its similarities with Mori Akira’s idea of “human becoming,” which adds a developmental angle to Watsuji’s tensional view of the human being. It then proceeds to sketch out how ethics and education emerge from the view of human being/becoming of both thinkers. Finally, it carefully analyzes the key problem of the “dual-negative structure”: How can we be good if goodness requires that we be both individual and collective, two aspects that are negatively related to each other? After showing Watsuji’s issues, it shows Mori’s contribution, which includes philosophical theory, scientific theories drawn from developmental psychology, and praxis drawn from Mori Akira’s textbooks.