The origin of this world, in which we live and move, is one of the important topics invariably discussed in the darśanas or the Indian philosophical systems. The Vedāntic systems, while agreeing that Brahman, the Absolute, is the ultimate cause of this world, are not unanimous about the way of evolution of the world from Brahman. While the Advaita system describes Brahman as the unchanging reality and hence, the world as only an illusory appearance foisted on it due to ignorance of its real nature, the Viśiṣṭā-dvaita system accepts that Brahman does transform itself as this world even as milk becomes curds. (pariṇāma = transformation).
Viśiṣṭādvaita Vedānta accepts Brahman (or Īśvara) as the primary reality and cit (the sentient beings, the jīvas or the individual souls) as well as acit (the insentient nature, also called prakṛti) as secondary realities dependent on Brahman. Brahman includes them in itself as an integral part, pervades them and transcends them. It is this acit or prakṛti part that really gets transformed.
This doctrine which accepts that Brahman transforms itself into this world through its prakṛti-part is known as ‘Brahma-pariṇāma-Vāda’.