This book, 'Brahma-Tattva Maula Sutra'- contains the carefully selected shlokas to depuct the Core Theosophy of Vendant, which are available only in a very much selected passages of the mukhya-upanishads. There is still some slight incnsiatencies and defferent explation of the same topic by different Upanishads, mainly becasuse, different persons in dfferent time, wrote UPANISHDIC VERSES AND PROSE, and unike other major Phylosophies OF iNDIA, WHICH WERE PROPOUNDED BY KNOWN PHILOSOPHERS, but in the case of Upanishad, the names of the speakers of the VEDANTIC THEOSOPHIES, were nick-names, and surely no renouwnd personality except BRAHMIN SAGE, YANAVALKYA, whose very understanding of Aatmma ds not tally with core concepts of Aatmma. anyway, as writer I tried to digging out the main shlokas to represent about a dozen of main and vital issues covered by the cre UPANISHADS, which at least includes-[a] Root-energy behind all creations [b] first poetical narration of the big-bang concept,[c] matter and energy equivalence [d] scientific fixation of the life-energy and it’s location in body, [e] reason of no-god, no-worship, no-ritual prescriptions, [f] reason of bonding with birth-death-rebirth-cycle, [g] value of enlightenment and types or forms of possible emancipations, as well as core Ethics of Human life.