The immune system as a supersystem.

I coined a term "supersystem" to designate highly integrated life systems such as the immune system, nervous system, and embryogenesis. While the mechanistic system is defined as a set of diverse elements so connected and related as to form an organic whole for a particular purpose, the "supersystem" engenders its own elements from a single progenitor. The diverse elements thus generated form relationship by mutual adaptation and coadaptation, and thus they create a dynamic self-regulating system through self-organization. It is a closed self-satisfied system, yet open to the environment, receiving outside signals to transduce them into internal messages for self-regulation and expansion. Unlike a mechanistic system, the "supersystem" has no defined purpose and determines its own fate by referring to its self-established behavioral pattern. Both the immune and nervous systems develop and function as a typical "supersystem." The prototype of the supersystem can be seen in embryogenesis and evolution. The concept of the supersystem can also be applied to the development of language, or a city, or other cultural phenomena that human beings have created as a result of their vital activities.