This article introduces the Leibnizian representations of Chinese writing and the Yijing hexagrams. I argue that Leibniz chose Chinese writing for his Universal Characteristic and then abandoned it because it was neither a combinatory nor a script that allowed calculation. His epistolary exchange with Bouvet revived his interest in Chinese writing with the analogy between binary arithmetic and the hexagrams of the Yijing established by the Jesuit. The hexagrams appear as combinatorial and therefore eligible to participate in Leibniz's project as signs. However, he is plagued by ambivalence, led by both the hope of building a Universal Characteristic from the hexagrams, and a caution against using them. Bouvet changed Leibniz's view of Chinese characters which he considered less pictographic and more philosophical because of their genealogical link with the Yijing hexagrams assumed by the two men.