Admiral Andrew Cunningham's autobiography shows why a source cannot be labelled primary or secondary in the abstract. Cunningham can be a primary witness to actions he directed or observed, while events reported to him may require a different evidential treatment. His location also matters: commanding at sea, directing operations ashore, and serving as First Sea Lord gave him different kinds of access. Define the research question, then identify the author's position, access to events, and likely perspective before judging the account.
Chapter · 6:27-8:09
Decide what kind of evidence a memoir provides
A memoir is primary evidence only for questions within the author's direct experience; its status depends on the question being asked.