The noosphere can be seen as the "sphere of human thought" being derived from the Greek νους ("nous") meaning "mind" in the style of "atmosphere" and "biosphere". In the original theory of Vernadsky, the noosphere is the third in a succession of phases of development of the Earth, after the geosphere (inanimate matter) and the biosphere (biological life). Just as the emergence of life fundamentally transformed the geosphere, the emergence of human cognition fundamentally transforms the biosphere. In contrast to the conceptions of the Gaia theorists, or the promoters of cyberspace, Vernadsky's noosphere emerges at the point where humankind, through the mastery of nuclear processes, begins to create resources through the transmutation of elements.
The word is also sometimes used to refer to a transhuman consciousness emerging from the interactions of human minds. This is the view proposed by the theologian Pierre Teilhard de Chardin, who added that the noosphere is evolving towards an ever greater integration, culminating in the Omega Point—which he saw as the ultimate goal of history. The noosphere concept of 'unification' was elaborated in popular science fiction by Julian May in the Galactic Milieu Series.