At a time, o Monks, when the monk thus trains himself: Perceiving the thoughts will I breathe in, perceiving the thoughts will I breathe out'; enlivening the thoughts will I breathe in, enlivening the thoughts will I breathe out'; 'concentrating the thoughts will I breathe in, concentrating the thoughts will I breathe out'; 'dissolving the thoughts will I breathe in, dissolving the thoughts will I breathe out': at such a time, o Monks, a monk examining thoughts observes the thoughts, unremittingly, with perspicacity and insight, after having conquered worldly desires and worry.

(Buddha Sakyamuni)