Asanga's path to perfection

What is a person who has only a single interval? It is a person who is a once-returner who reaches the end of suffering by living only among the gods. What is a person who attains Nirvana in the intermediate state? It is a person who, when the fetters of rebirth are destroyed but when the fetters of continuity (to advance) are not yet destroyed while advancing towards the intermediate existence confronts the Path and puts an end to suffering; or who, having advanced in the intermediate existence while thinking of going to a rebirth existence, confronts the Path and puts an end to suffering; or who, having reflected and set out towards a rebirth existence, without however arriving at the rebirth existence, confronts the Path and puts an end to suffering.

— from the Abhidharmasamuccaya of Asanga

Asanga (4th Century) was an Indian philosopher and leading figure in the Yogacara tradition in India, considered with his half-brother Vasubandhu to be the founder of this school of Buddhist thought. The Yogacara school sought to understand perfection through a study of being and the study of how one comes to know. In the Abhidharmasamuccaya (“A Compendium of Abhidharma”), Asanga sought to analyze and systematize the mental processes by which one followed the path to perfection.