大乘義章 1.124

1.124

第一釋名。如、法性、實際義，出《大品經》，此三乃是理之別目。故龍樹言：如法性等，實相異名。所言如者，是其同義。法相雖殊，理實同等，故名為如。言法性者，自體名法，法之體性，故云法性。言實際者，理體不虛，目之為實，實之畔齊，故稱為際。名義如是。

First, explaining the names. The doctrines of tathatā (如), dharmatā (法性), and bhūtakoṭi (實際) derive from the Pañcaviṃśatisāhasrikā-prajñāpāramitā Sūtra; these three are different designations for the principle. Thus Nāgārjuna states: "Tathatā, dharmatā, and so forth are different names for the true mark." That which is called tathatā (如, "suchness") has the meaning of sameness (同). Although the characteristics of dharmas are different, in their true principle they are identical; hence it is named tathatā. That which is called dharmatā (法性, "dharma-nature"): the intrinsic essence is called dharma, and it is the essential nature of dharmas; hence it is called dharmatā. That which is called bhūtakoṭi (實際, "reality-limit"): the essence of the principle is not false, which is designated as real (實); the boundary and limit of the real is therefore called the limit (際). The nominal meanings are like this.