What is critical yeast?

The term "critical yeast" is a metaphor used by John Paul Lederach to describe a crucial element in societal change and transformation. Unlike the physical concept of critical mass, which implies a large quantity, critical yeast signifies the critical importance of quality within small groups or interactions. It emphasizes the role of small, high-quality interactions that can set the stage for larger changes. This metaphor highlights how even small numbers of interconnected, committed individuals can initiate significant social, cultural, and community transformations by fostering deep trust and relationships. The "critical yeast" functions as a catalyst, indicating that real change often begins with small, meaningful acts carried out by a few individuals, which then spread and grow throughout a society 1 2.