There are two purushas in the world — the perishable and the imperishable. All beings are the perishable; the unchanging essence is called the imperishable. Shankara distinguishes the ever-changing phenomenal world from the unchanging witness-consciousness. Ramanuja identifies the perishable as the body-matter complex and the imperishable as the individual soul. The Bhakti tradition sees this distinction as preparation for understanding the Supreme who transcends both. Madhva explains these as genuinely distinct categories — perishable beings subject to change, and the imperishable unchanging essence of souls — with God transcending both. Abhinavagupta reads them as two aspects of consciousness: the kshara identified with changing forms, and the akshara in its undifferentiated state. Vallabha teaches that both are real and divine, but God as Purushottama transcends both as the complete reality. Tilak finds this essential: the world of action is real, eternal principles are unchanging, and the Supreme gives ultimate meaning to both. Vivekananda sees this as the Gita's clearest philosophical framework: change, changelessness, and the Absolute beyond both.