Abstract: as a famous modern philosopher,logician,Feng Qi has made a landmark exploration on logic category.He elucidated the dialectical nature and characteristics of logic category,saw about the logic category system and the dialectical movement of cognition,established the logic category system with detection,reasoning and cause￣finding as its framework and probed into the significance of the methodology of the logic category system.

Key words: Feng Qi, logic category, dialectical movement of cognition, methodology, detection,reasoning and cause-finding