三观
The three studies, meditations, or insights. The most general group is that of Tiantai: (a) 空观 study of all as void, or immaterial; (b) 假观 of all as unreal, transient, or temporal; (c) 中观 as the via media inclusive of both. The Huayan group is 空观, 理事无碍观 and 周遍含容观, see 华严经:法界观. The 南山 group is 性空观, 相空观, and 唯识观. The 慈恩 group is 有观, 空观 and 中观.