Plurality Is Not the End Point: From Civilizational Coexistence to Civilizational Integration—Non-Coercive Integration, Cultural Evolution, and the Formation of a Shared Civilizational Layer

Cultural diversity is a basic reality of human civilization and an important source of knowledge, meaning, identity, and creativity. Yet acknowledging civilizational plurality does not answer a further question: must different civilizations remain permanently parallel, or can long-term contact, comparison, practical testing, and mutual learning generate new shared structures? If unity is overemphasized, theory can slide into assimilation, hegemony, and cultural erasure. If plurality itself is treated as an untouchable final state, however, historically contingent civilizational boundaries may become frozen, obscuring the fact that human civilizations have always changed through diffusion, borrowing, translation, hybridization, and re-creation. Within the framework of the Human Happiness Community, this paper develops the concept of non-coercive civilizational integration and proposes a Civilizational Integrative Evolution Model (CIEM). Civilizational integration, as defined here, does not require civilizations to abandon their languages, religions, arts, historical memories, or ways of life, nor does it presuppose that all societies will eventually adopt identical institutional structures. It refers instead to a process in which civilizations retain subjecthood and legitimate differences while, through sustained contact, cross-cultural translation, comparative evaluation, selective adoption, recombination, and localization, some bodies of knowledge, norms, technologies, institutional experience, and value achievements move from particular civilizational origins into wider systems of shared human use. In that process, new structures may emerge that no single civilization could have produced independently. The paper engages theories of cultural diversity, acculturation, multiple modernities, cultural hybridity, and cumulative cultural evolution. UNESCO treats cultural diversity as a common heritage of humanity while also emphasizing intercultural exchange, dialogue, and cooperation. Berry's acculturation framework distinguishes assimilation, separation, marginalization, and integration, showing that maintenance of one's original culture need not conflict with active participation in a larger society. Eisenstadt's theory of multiple modernities challenges the idea that Western modernization represents a single template toward which all societies must converge. Bhabha's discussion of hybridity and the 'Third Space' shows that cultural encounters can generate new structures of meaning rather than merely preserve two unchanged traditions or allow one to replace the other. Research on cumulative cultural evolution further emphasizes humanity's capacity to preserve, transmit, and improve achievements beyond the creative capacity of any isolated individual. On this basis, the paper proposes a seven-stage mechanism of civilizational integration: coexistence of difference, sustained contact, meaning translation, comparison and practical testing, selective adoption, recombination, and formation of a shared civilizational layer. The shared layer does not abolish existing civilizations. It produces a nested structure of higher-level sharing and lower-level diversity. The paper also argues that integration must remain constrained by autonomy, reciprocity, non-domination, revisability, respect for subjecthood and dignity, and long-term sustainability. A higher-order unity, if it emerges, should therefore not be understood as cultural uniformity, but as the expansion of shared interests, the accumulation of shareable civilizational achievements, the decline of hostile boundaries, and the strengthening of a common human identity. The central thesis is straightforward: plurality need not be permanently frozen as history's end point, and unity cannot legitimately be manufactured in advance by power. The real theoretical problem is how plural civilizations, under non-coercive conditions, can generate higher-order shared structures through long-term interaction.