brahmam as per vedanta

all the systems of vedanta address these issues: tatva, hita, purushartha. they differ in the way they define them. tatva is accepted by all the schools as brahmam. advaitha says brahmam is undifferentiated pure consciousness and it cannot be defined by attributes. it is nir-vishesha. the Shruthi says "neti neti" and sri sankara intreprets it as sublation of all the qualities and reducing it to an undifferentiated consciousness. Ramanuja uses "aparkta siddhi" and says that non differentiated substance cant be inferred or perceived and thus says that brahmam is a unified congloromerate of all the auspicious qualities.
So vishishtadvaitha treats brahmam as an omni-potent eshwara i.e Narayana who has svabhava and svarupa and who is of the substratum of suddha satva . suddha satva is one of the "dravyas" which gives rise to "Dharma bhuta gnayna" or attributive consciousness . this consciousness reveals other objects and through "dharmi gnayna" brahmam realises and revels in its own bliss. Brahmam has its body composed of jeevas and achit and it associates with them in a very complex relationship explained as "samana adikarana" which roughly can be described to a body -soul relationship. dvaitha's brahmam is similar to vishitadvaitha's brahmam but differs in relationship with chit and achit. Desika says in virodha pariha that nature of liberation is such that the attributive consciousness gets merged with that of Narayana but dharmi state remains that gives seshatvam . thus through coordinate predication Ramanuja says brahmam is some thing changeless but exists alone qualified by manifold attributes and subordinates like achit and jeevas.

Madva says that there is complete difference between brahmam and jeevas and no union ir co-existence is possible.

Nimbarka says that both manifoldness and unity co-exist in brahmam."ajayamanah bhaudavi jayathe" of vedas says that the changless -beginningless brahmam grows into manifold .

vallabha opies that brahmam alone is the tatva and jeeva and achit are self modifications done by brahmam on itself as a sport.

but Ramanuja-Desika's system seems best to give a single coherent picture of bheda shuritis and abedha shruthis.