Litui and the Logical System of Qionglixue

Qionglixue (穷理学) is the only known text from the late Ming and early Qing periods that directly translates and introduces content related to logical reasoning. The term litui (‘理推’) is the key to understanding and interpreting Qionglixue, corresponding to Latin terms Syllogismus and Ratiocinatio, and thus carries dual connotations of ‘syllogistic form’ and ‘rational inference’. The character tui (‘推’) signifies a dynamic process of moving from one to another, while the character li (‘理’) embodies the creative translation of rationality by the missionaries, revealing the close connection between rationality and inference. The definition of litui in the Qionglixue encompasses the fundamental characteristics of the Aristotelian syllogism. Two closely related terms, tuilun (‘推论’, reasoning) and tuibian (‘推辩’, argumentation), further elaborate the meaning of litui from perspectives of reasoning and argumentation, respectively. Terminologically and conceptually, litui stands as the most central term and concept in the logical system of Qionglixue. Moreover, within Ferdinand Verbiest's ‘Qionglixue’ knowledge system, which is centered on logic, litui also serves as the thread linking various fields of Western knowledge and constitutes their fundamental methodology.