  Artificial, neurobiological, and social networks are three distinct complex
adaptive systems (CAS), each containing discrete processing units (nodes,
neurons, and humans respectively). Despite the apparent differences, these
three networks are bound by common underlying principles which describe the
behaviour of the system in terms of the connections of its components, and its
emergent properties. The longevity (long-term retention and functionality) of
the components of each of these systems is also defined by common principles.
Here, I will examine some properties of the longevity and function of the
components of artificial and neurobiological systems, and generalise these to
the longevity and function of the components of social CAS. In other words, I
will show that principles governing the long-term functionality of computer
nodes and of neurons, may be extrapolated to the study of the long-term
functionality of humans (or more precisely, of the noemes, an abstract
combination of existence and digital fame). The study of these phenomena can
provide useful insights regarding practical ways that can be used in order to
maximize human longevity. The basic law governing these behaviours is the Law
of Requisite Usefulness, which states that the length of retention of an agent
within a CAS is proportional to the contribution of the agent to the overall
adaptability of the system. Key Words: Complex Adaptive Systems,
Hyper-connectivity, Human Longevity, Adaptability and Evolution, Noeme
