In the Saṁdhinirmocana Sūtra, the third wheel focuses on "differentiation," namely that three natures of all phenomena should be discerned: the constructed (kun brtags pa'i mtshan nyid, Skt. parikalpita-lakṣaṇa), the dependent (gzhan dbang gi mtshan nyid, Skt. paratantra-lakṣaṇa), and the thoroughly established (yongs su grub pa'i mtshan nyid, Skt. pariniṣpanna-lakṣaṇa). The third wheel also belongs to Mahāyāna, but is more closely associated with the Mind-Only School. Other traditions focus instead on the third wheel's association with the Buddha-nature (de bzhin gshegs pa'i snying po, Skt. tathāgatagarbha) sūtras and their teaching of a luminous Buddha-nature existing in all life.