# Diagnosticity matrices

_When two or more concerns could each explain the same symptom, we open a [diagnosticity matrix](https://en.wikipedia.org/wiki/Analysis_of_competing_hypotheses) and evaluate evidence row-by-row across the competing concerns. Evidence consistent with all concerns has zero diagnostic value; evidence that contradicts only one is decisive. We rank by inconsistency — the concern with the most contradicting evidence is rejected first. Linchpin evidence (single-point-of-failure for the leading hypothesis) is flagged explicitly._

_No diagnosticity matrices recorded._