ME.19:10 - Rationale

Differentiation history, causal support, and present choice have different subjects and truth conditions. A dated sequence can be accurate while its causal explanation is unsupported; an unsupported causal claim can coexist with a useful non-causal design constraint; and neither supplies present authority.

The pattern connects questions about variant generation, transmission, fashion, retention and loss. Evolutionary analogies and search-frequency examples can suggest hypotheses and rivals; their causal use depends on diagnostic observations. Process-tracing sources strengthen that inquiry. C.28 states what support a causal use needs, keeping a plausible narrative separate from identification or estimation.