The ancient proverb Junri-Sokuyu ("Adhering to Reason Leads to Prosperity") was one of the personal mottos of Toyobo’s founder, Eiichi Shibusawa, and is the fundamental principle for Toyobo today. Eiichi Shibusawa was one of the modernizers of Japan during the early 20th century, helping to found and develop more than 500 companies.
The phrase Jun-ri-Soku-yu is composed of four Chinese characters, the second of which ("ri") has the dual meaning of "reason" and "ethics." It expresses the idea of thinking and acting rationally and logically, as well as the need to retain respect for morality and ethics, the fundamental nature of being human, and an ethical sense of values.