Informational permeability is the constitutional principle of signal access:
No model of the ecology may become more authoritative than the ecology’s continuing ability to update it.
That is stronger than transparency. Transparency lets you see the model; permeability demands that the model stay correctable by reality — that fresh, dissenting, local, and anomalous signal can always reach and revise it.
What it requires in practice
Permeability implies many independent information channels; open access to non-sensitive public data; strong protection for dissent and whistleblowing; mechanisms for local observation to reach larger systems; rapid correction of known errors; visible uncertainty; provenance for data and models; minority and anomaly reporting; protection against information monopolies; and AI that exposes competing interpretations rather than collapsing everything into a single answer. It is the informational sibling of contestable metrics and of the no-monopoly-over-what-matters principle — a system that cannot be updated by what is actually happening has already begun to fail. See Signal Access.