起信論疏筆削記 4.30

4.30

Third, explaining the word "ocean" (海). The point of doubt and the intended explanation can be known from the Commentary. Regarding "inferring and contemplating the dharma accordingly", one should say: Tathatā accords with conditions to produce defilement and purity; though defilement and purity are produced, tathatā remains unchanging. The unchanging nature does not obstruct defilement and purity; the myriad distinctions of defilement and purity do not obstruct the single nature. Therefore, nature and characteristics are non-dual. For this reason, the single word "ocean" is used to metaphorically illustrate that tathatā accords with conditions while remaining unchanging.