注大乘入楞伽經 3.78

3.78

言外道以無常變異相為常不思議因故云常，非是自覺所行相因力故常。

This means that the heterodox take the characteristics of impermanence and mutation as the cause of the permanent and inconceivable, and therefore call it permanent; it is not permanent through the causal power of the characteristics practiced in self-realization.