Werbos's 'credit assignment' and Amari's 'five-layer MLP' are independent instances of Skinner's mythology of doctrines

historiographyquentin-skinnermythology-of-doctrinesmyth-ledgerwerbosamaribackpropagation-originssynthesis

Skinner's mythology of doctrines names the error of "converting some scattered or quite incidental remarks by a classic theorist into his 'doctrine'" — attaching a vocabulary or systematic framework to a text that never articulated it. Two cases from the vault's backpropagation-origins myth-ledger fit this shape by the same mechanism, not by loose analogy: a later commentator supplies a specific term the original text does not contain, then treats the text as though it had used it.

• Werbos, "credit assignment." claim-werbos-1974-no-credit-assignment-language establishes, by direct grep over the cached full-text extraction of Werbos's 1974 thesis, that the words "credit" and "assignment" occur zero times in the document. The retrospective label "backprop solves spatial credit assignment (Werbos 1974)" credits the thesis with a named technical achievement it never states in its own words.
• Amari, "five-layer MLP with two modifiable layers." myth-amari-first-sgd-mlp and claim-amari-1968-saito-experiment-primary-read establish, by direct OCR read of Amari's 1968 book (pp. 94–135), that "layer"/"multilayer" vocabulary is absent from the span describing the Saito experiment; the model described is a piecewise-linear discriminant, not an MLP in the book's own terms. "Five-layer MLP" is Schmidhuber's later re-description.

Two independent instances sorting the same way strengthens "mythology of doctrines" as the vault's label for its term-crediting cluster specifically — distinct from the category-projection cluster (prolepsis) that claim-skinner-prolepsis-and-doctrines-name-two-modes-of-the-vaults-back-projection-pattern first split off, using Werbos alone.