This paper argues that AI reasoning over relational and temporal evidence is fundamentally a topological problem. When an AI system processes evidence such as security events, medical records, engineering telemetry, or financial transactions, it is traversing a graph whose structure encodes causal constraints, temporal ordering, and integrity boundaries. Whether such reasoning can be certified is therefore not primarily a behavioural question. It depends on structural properties that are invariant under representation changes, namely topological invariants of the evidence graph. We develop this claim in two parts. Part I establishes the mathematical foundations. It explains why graphs are the natural representation for evidence-centric reasoning, how topological invariants constrain what can be inferred without introducing spurious dependencies, how genus characterises the complexity of the reasoning surface, and how bridges, reachability, and non-orientability map to forensic and safety-relevant notions such as single points of failure, causal isolation, and integrity violations. Part II presents ER-topo.cert, a concrete architecture for operational topological certification. It introduces a portable certificate format encoding rotation systems and wrap–shift ledgers, a deterministic graph identity check in O(E log E)and an O(E) dart-walk verifier, and a three-mode protocol that provides explicit contractual guarantees under varying producer trust and compute constraints. The result is a framework in which the structural integrity of AI reasoning can be proved as a property of the evidence graph rather than inferred indirectly through post-hoc behavioural testing.
Erkan YALÇINKAYA (Wed,) studied this question.