Influence: Gaining Commitment Getting Results 2e (French for Canada) PDF or paste a DOI name into the text box. Jump to navigation Jump to search For the use in computer science, see Computational complexity.
This article may need to be rewritten entirely to comply with Wikipedia’s quality standards. The discussion page may contain suggestions. Complexity characterises the behaviour of a system or model whose components interact in multiple ways and follow local rules, meaning there is no reasonable higher instruction to define the various possible interactions. The term is generally used to characterize something with many parts where those parts interact with each other in multiple ways, culminating in a higher order of emergence greater than the sum of its parts. The study of these complex linkages at various scales is the main goal of complex systems theory. Many definitions tend to postulate or assume that complexity expresses a condition of numerous elements in a system and numerous forms of relationships among the elements.
Warren Weaver posited in 1948 two forms of complexity: disorganized complexity, and organized complexity. Some definitions relate to the algorithmic basis for the expression of a complex phenomenon or model or mathematical expression, as later set out herein. Weaver perceived and addressed this problem, in at least a preliminary way, in drawing a distinction between « disorganized complexity » and « organized complexity ». In Weaver’s view, disorganized complexity results from the particular system having a very large number of parts, say millions of parts, or many more. Though the interactions of the parts in a « disorganized complexity » situation can be seen as largely random, the properties of the system as a whole can be understood by using probability and statistical methods. A prime example of disorganized complexity is a gas in a container, with the gas molecules as the parts.