Cultural Additivity Theory

This paper presents Cultural Additivity Theory (CAT) as a process framework for explaining how cultural systems interact, absorb, transform, and recombine information-value bundles. While the term cultural additivity was pioneered by Vuong et al. (2018) to analyze the syncretic nature of Vietnamese folktales, it has not yet been elaborated as a general theory of cultural interaction. This study addresses that gap by defining CAT as a continuous process in which agents, situated in natural and social environments, process information-value bundles in pursuit of survival and sustainable development. CAT is articulated through four core components, a three-level hierarchy of interaction (exchange, compatibility, and resonance), and a value-comparison formula that admits linear, super-additive, and sub-additive outcomes. The theory further identifies three erosive mechanisms: conflict-driven destruction, high-entropy capacity strain, and low-entropy structural lock-in. By examining theory-illustrating cases ranging from funeral rites to the highadditivity paradox of Vietnamese culture, the paper shows how CAT can function both as an analytical lens and as a generator of empirically testable hypotheses for studying cultural resilience, innovation, and erosion in the modern world.