觀空相之禪定。通於內外。內道之空定，三三昧是也。外道之空定，四無色定是也。亦曰四空定。是雖空諸法，而獨不能空我，故還輪迴於三有。大日經疏七曰：「若深求此中至[泳-永+頤]，自然撥除因業，唯我性獨存，乃至無一法入心，而證空定，最是世間究竟之理。是故垂盡三有，還墮三途。」
The meditation which dwells on the Void or the Immaterial; it is divided into 內道, i.e. the 三三昧, and 外道, the latter limited to the four dhyānas 四空定 q.v., except the illusion that things have a reality in themselves, as individuals 法我 q.v.
觀察空相的禪定。