Linear narrative is the wrong abstraction for verified reasoning. A line has one path; a graph has many. Quantm represents every problem internally as a directed graph of data nodes, where each node carries a typed value, a domain of validity, and a list of which other nodes contributed to it. The graph is not a visualisation. It is the working representation the engine computes against.
This topology is what makes structurally independent verification possible. To verify a result, the engine looks for a second path through the graph that arrives at the same node from a disjoint set of predecessors. If such a path exists and the two arrive at agreeing values, the joint probability of a coherent silent error collapses. If no second path exists, the engine flags the result as single-path — which is not the same as wrong, but it is honest about the verification depth that was actually achieved.
The graph also makes failure fixable. When a derivation collapses, the engine can point to the exact node where the contradiction was detected and the exact predecessors that produced it. There is no opaque mid-chain failure; the topology turns every error into a locatable defect. That is the operational meaning of traceability — and it is only available because data nodes are first-class objects in the architecture, not implementation detail buried under a prose surface.