If a system can continue to reproduce itself (i.e. exist) over time, it is referred to as a viable system.
Viability is a function of, amongst other things, feedback and variety, and just as for these concepts it emerged from the field of cybernetics.
Every viable system is contained in other viable systems (see holon).
The cybernetician Stafford Beer developed a rigorous appreciation for viability through his development of the Viable Systems Model.