Nirguna brahman as pure being, existenc consciousness, bliss. What is it to us? You are that tat tamasi. This idea is therein when sami vive kande says, shiva gane jiva sewa e formula he got from sirama krishna. But again, it is worship who pass siabrahma, the world brahman to be worshipped. So these are the three conceptions. Deta ve danta is primarily the first conception; Bisista dweta ve dante is the second and adweta vedantesprimarily the third.