Definition

A hierarchic system is composed of interrelated subsystems, each of which is itself hierarchic in structure, continuing until reaching some lowest level of elementary subsystem.

Key Points

1. Flexibility of elementary subsystems:

   • The choice of elementary subsystem is often arbitrary

   • Depends on the purpose and context of the study

   • Examples:

     • Physics: from elementary particles to atoms to stars

     • Biology: from amino acids to proteins to cells

2. Broader interpretation of “hierarchy”:

   • Not limited to systems with authority relations

   • Includes systems without subordination among subsystems

   • Encompasses all complex systems analyzable into successive sets of subsystems

3. Distinction from formal hierarchy:

   • Formal hierarchy: specific authority relations (e.g., organizational chart)

   • Simon’s hierarchy: more general, including complex inter-part relations

4. Scientific practice:

   • Scientists often treat complex subsystems as elementary

   • This simplification is usually valid if done carefully

Implications

• Allows for flexible analysis of complex systems at different levels

• Enables study of systems with diverse types of inter-component relationships

• Facilitates understanding of complex systems across various disciplines