Icard's 2024 dynamic logic resolves the reliability/credibility independence problem by abandoning independence — credibility becomes primary, reliability a dynamic update operator on it

intelligence-tradecraftepistemicssource-evaluationformal-logicdynamic-epistemic-logicadmiralty-codecross-domain-bridge

The vault's existing note on Kelly et al. (2025) records that paper's citation of "Icard (2023, 2024)" as a richer alternative to the Admiralty Code's two-axis scale — but that note explicitly flagged the primary as unread, working only from Kelly et al.'s citation-of-a-citation. Reading Benjamin Icard's own 2024 paper (LIP6 Sorbonne Université / Institut Jean-Nicod) shows something more specific than "richer structure": Icard's dynamic logic L(intel) does not keep reliability and credibility independent at all. It makes credibility the sole primary evaluative dimension, with reliability demoted to a dynamic operator that updates credibility rather than standing beside it as a second axis: "We adapt dynamic belief revision to make credibility the main dimension of evaluation and introduce dynamic operators to update credibility ratings with the source's reliability."

The motivation is explicit in the paper: intelligence officers "perceive credibility as a more important dimension then reliability" (sic) during evaluation, in tension with NATO doctrine's independence requirement — the same empirical failure the vault already tracks via claim-source-reliability-and-credibility-are-not-judged-independently and the cross-domain RAG convergence. Where the open question about the vault's own source_tier design has so far framed the choice as fuse-into-one-number versus keep-two-independent-axes, Icard's logic is a third shape: two named quantities that are formally not independent by construction, one subordinate to the other.

See also

claim-icard-2023-taxonomy-nine-honesty-truth-message-types — the separate, earlier taxonomy Icard's own reference [5] traces this proposal back to.