This is a mental model used in various fields to understand complex systems or relationships by breaking them down into three interconnected parts.
The Law of Three is a mental model that suggests to optimally solve any problem, or to understand any relationship, it can be helpful to think in groups of three. This can be observed in everyday life, such as 'beginning, middle, end' in storytelling or 'thesis, antithesis, synthesis' in philosophy.
For instance, in project management, a project can be understood and managed better by considering three factors: Time, Cost, and Quality. Neglecting any one of these can adversely impact the other two and therefore the project's success. It demonstrates the interconnectedness of the components and provides a holistic view while looking for solutions.
'Triangular thinking is an essential tool for understanding complex, dynamic situations.' - Jamshid Gharajedaghi
