Natural foundation for a sustainable development: physical, chemical and biological envelopes of viability. -The general properties of 1ife Wilderness (cellular and ecological logic), that strengthen since several billion years a viable and dynamically sustainable development of living species (biospace) are compared with the human society activity, in order to detect the gap between (renewable energy, climatic thermic effect, biomass and demography, water, etc.). The concept of physical, chemical and biological envelopes of viability is presented, as the way to circumscribe in the ecospace, after identification of the few planetary limits, a sustainable and culturally differentiated human activity on the planet