Systemic Definitions of Sustainability, Durability and Longevity

The sustainable progress of humanity requires a rigorous definition of concepts, models and ways of realization. Sustainability, durability, longevity are key concepts. This paper explores the current definitions of sustainability while sustainability is examined critically. Then are defined, in a systemic manner, using a functional segmentation model of external environment, of resource categories and products of anthropogenic systems: (1) the concepts of sustainability / durability / temporarity / ephemerality of system categories, (2) longevity as the life duration (of existence, functioning and behaviour) of an i-type specimen within the category of systems under consideration. The systemic definition and ranking of influence factors allow future improvements of practical ways of assessing, planning and implementing sustainability / durability and sustainable / durable progress at various hierarchical levels of Humanity.