It is on account of the feedback mechanism that the system persists even though everything associated with it may change continuously and radically.
4. Political system is an open system amenable to the influence of environmental factors. It can be distinguished from other systems by boundary lines.
Outside and beyond the political system there are other systems or environments that may be distinguished from each other.
5. The environment of a political system may be intra societal as well as extra-societal.
6. A political system always remains subject to challenges from forces operating in the environment, which is required to cope with. Easton calls such forces as stresses that constitute the response mechanism of the political system.
The stresses are of two kinds—demand stress and support stress.
7. Political system may be in a steady state if there is proper balance between inputs and outputs.
Inputs are demands made upon the political system and the support of the system itself; Supports are those processes or structures which give it the capacity to cope with the demands made upon it.
Outputs are the results of the processing of demands.
There may be with inputs as the demands made by the political elites themselves.
8. A political system lives in a critical range— inputs have an overload.
9. The survival of a political system requires certain structural bases that may be in the form of institutional arrangements like electoral machinery and political parties and non institutional arrangements in the form of political beliefs and attitudes of the people.
10. The political system, apart from being a system in itself, consists of subsystem (mediating groups) involved in the decision making process, what Easton calls Para political system.
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