Gall’s Law

Gall’s Law posits that effective complex systems evolve from simpler, functional predecessors. Widely applied in fields like engineering and organizational design, the principle advocates for an iterative development process that starts with basic, operational systems.


Gall’s Law posits that complex systems that work evolved from simpler systems that also worked.

Key Elements

  • Simplicity at Origin: Argues that a complex system must start from a simple system and then grow in complexity.
  • Functional Evolution: Specifies that the simple system must be functional and working for it to evolve into a complex system that also works.
  • Inversion Doesn’t Hold: A complex system designed from scratch is unlikely to function as intended.
  • Iterative Development: Implicit in Gall’s Law is the iterative process, i.e., simple systems undergo modifications and additions to evolve into more complex ones.

Practical Implications

  • System Design: Often cited in software development, engineering, and organizational design where the principle is to start simple and iterate.
  • Failure Analysis: Provides a framework to analyze why complex systems fail; often, it is because they were not allowed to evolve from simpler, functional systems.
  • Adaptability: Simple systems are easier to adapt, which increases the probability of the evolving system to continue functioning.
  • Risk Mitigation: Starting with a simpler system minimizes the risks associated with complex systems, including costs and failure rates.


  • Not a Universal Law: Does not apply to all systems in all contexts. Some complex systems may require initial complexity for basic functionality.
  • Ambiguity in ‘Working’: The term ‘working’ can be subjective and context-dependent.

Global Perspective

  • Sociopolitical Systems: Can be applied as a critique or analysis tool for governance models and organizational structures across cultures and countries.
  • Economic Theories: Used in the context of evolving economic models and market systems.
  • Cultural Evolution: Has implications for understanding how cultural norms and practices evolve over time.
  • Scientific Models: Utilized to understand how scientific theories and models evolve from simpler explanatory frameworks.