"Dira Betachtonim" () is the process of manifesting the presence of God within the world. An examination of "Dirah Betachtonim" is found in "Samech Vov" by the fifth Chabad Rebbe, Rabbi Sholom Dovber Schneersohn. In "Samech Vov", this concept is described as the ultimate purpose of creation. "Dirah Betachtonim" is also explored by the seventh Rebbe, Rabbi Menachem Mendel. Central to the "Dirah Betachtonim" concept is the notion of sublimating the physical aspects of existence. In Chabad philosophy, "yeshut" ("selfhood" or "self-assertion") is seen as the antithesis to "yichud" ("unity"), a denial of the reality that God "fills the heavens and the earth" and that there is none besides Him. "Bitul Hayesh" means total self-negation and a conscious awareness of the ultimate nature of man. "Bitul Hayesh" is achieved by one's reflection on God's greatness, exaltedness and majesty. For when one feels that they are in the presence of God, they will feel a sense of insignificance and humility. And at the same time, the worshiper will feel a passionate adoration for God, and a desire to cleave to God. A number of other important concepts in Chabad philosophy are referenced in scattered locations in Chabad literature. Though these topics were discussed in brief and were not the focus of any major work, new insights have been drawn from their treatment in Chabad thought. In its earlier formulations, Hasidic thought had elevated the rebbe to a level above that of typical hasid. A rebbe was closer to God, his prayers were more amenable to Him, and a hasid should satisfy himself with attachment to the Rebbe and hence indirectly to God. A rebbe was to be a living example of perfection and would concern himself with intellectualism on behalf of the followers. According to Sacks, Chabad stressed the individual responsibilities of every Jew: "The rebbe...became more of a teacher and adviser, recognising the vocation of each of his followers, guiding them towards it, uncovering their strengths, and rejoicing in their achievements." In Chabad thought, the Rebbe is not an intermediary between the Hasid and God. Rather, the role of the rebbe was to train followers to become spiritually self-sufficient and to turn to their Rebbe for instructions rather than intercession with God, miracles or blessings.