We can now no longer postpone the recognition of a second Sub-branch of theoretical science. It is a department perfectly well recognized. It belongs by virtue of its purpose to the branch of Theory; yet varies enough in its purpose from the active science to be erected into a Sub-branch. It is the subject of Humboldt’s Cosmos, Comte’s Philosophie Positive, and Spencer’s Synthetic Philosophy. It is science en retraite, Wissenschaft a.D. Its design is to sum up the results of all the theoretical sciences and to study them as forming one system. It may be called retrospective in contradistinction to active science.
The editors of the Collected Papers added "or science of review" after Peirce's designation "retrospective" at CP 1.256. In a variant of the passage in question, Peirce did use the term "reviewing science", so the attribution of synonymity appears to be justified.
…since the beginning of the nineteenth century, when Coleridge so defined it in the opening dissertation to the Encyclopaedia Metropolitana, non-scientific people have generally understood “science” to mean systematized knowledge.
The present writer [—] will call science in the Coleridgean sense retrospective science.