Contact between civilizations is logically reducible to four states: Elimination, Integration, Concealment, and Standoff. The Civilization Interface Hypothesis (CIH) proposes a theoretical framework describing the behavioral logic of intelligent civilizations. The hypothesis takes natural selection as its axiom—civilizations not driven by survival are systematically selected out, thus civilizations participating in cosmic competition are necessarily driven by survival and development—and rests on one core hypothesis: reproductive isolation is rare at cosmic scale, and species boundaries are not a universal concept among intelligent civilizations (H1). From this, four core propositions are derived: Interface compatibility is the core competitive capability of civilizations (P1); advanced civilizations tend toward network-distributed structures, composed of fixed stellar nodes, mobile fleet nodes, and probes (P2); advanced civilizations tend to establish Protected Zones around emerging civilizations, maintaining covert surveillance, conducting study, and deferring decisions (P3); in civilization systems without reproductive isolation, technological integration constitutes colonization, and expansion through integration is far faster than physical occupation (P4). This hypothesis applies to civilizations that have crossed the threshold of low-latency interstellar communication technology, and is validated on the basis of logical coherence and indirect observational support.
Yu Xie (Fri,) studied this question.