大般涅槃經義記 3.299

3.299

下廣之，「不知親近善知識故修無我」者，謂不親近大乘知識，專修無我。「亦復不知無我處」者，不知無我正在有為。「尚自不知無我真性，況復能知有我性」者舉淺況深，明不知我，舉淺擬深是以言「尚」。法空以為無我真性，一切諸法實無我故，二乘之人但知生空，不解法空，名為不知無我真性。無我易解，猶尚不知，況復能知有我真性？

Below, it expands upon this: "Because of not knowing to draw near to good spiritual friends, they cultivate selflessness" means that they do not draw near to Mahāyāna spiritual friends, but cultivate selflessness exclusively. "Nor do they know the locus of selflessness" means that they do not know that selflessness pertains precisely to conditioned phenomena. "When they do not even know the true nature of selflessness, how much less can they know the nature of having a self?": this adduces the shallow to contrast with the deep, clarifying that they do not know the self; adducing the shallow to measure the deep, it therefore says "even." Emptiness of dharmas is taken as the true nature of selflessness, because all dharmas are truly selfless; practitioners of the two vehicles only know the emptiness of persons and do not understand the emptiness of dharmas, which is called not knowing the true nature of selflessness. Selflessness is easy to understand, yet they still do not know it; how much less could they know the true nature of having a self?