The present paper studies meditation using the breath, one popular Buddhist technique, with emphasis on what Chih-yi called "the six marvellous doors. " A review of the extant relevant literature including the early sutras, the Vinayapitaka as well as later treatises and meditation texts but excluding for the time being works by contemporary authors&, makes it possible to trace the development of "the six marvellous doors. " Development here refers to both change in the number of stages ("six marvellous doors" etc.) and diversity in terms of explanations given the stages themselves. It also becomes clear that, besides differences in individual meditational experience and understanding, one factor leading to the development of the meditation using the breath was that the soteriological schemes propounded by different Buddhist schools varied.
