A document from the period you are studying can feel reassuringly close to the action. It is tempting to treat that closeness as a stamp of reliability. A better starting point is curiosity: this source lets you hear a particular voice, under particular circumstances.
That voice might preserve valuable evidence while leaving other things unstated. Your task is to work out what question it can help answer.
Ask what makes it primary for your question
Harvard Library’s guide describes primary sources as direct or firsthand evidence connected to the subject under study. A later memoir can also serve as a primary source, and a digital copy or translation does not automatically stop a source from being primary. The relationship to the research question matters more than the file format.
Suppose you are studying how a writer remembered an event twenty years later. A memoir could be central evidence for that act of remembering. If you instead want the exact words spoken at the original event, the same memoir calls for a different kind of caution. That is an illustrative scenario, not a claim about a particular historical memoir.
Put the audience beside the author
Before collecting striking sentences, make a compact source card. Who produced the document? Who was expected to read or hear it? What kind of document is it? Where did your copy come from? Which parts are missing or supplied by an editor?
A private note, a public defence and a ceremonial speech may each make different choices about what to explain. You do not need to decide that one is “good” and another “bad” before examining those choices. Begin by identifying the work the document is trying to do.
Keep observation separate from inference
Use two columns in your notes. In the first, record what you can point to directly: a repeated word, an address to a named audience, a gap in the surviving text. In the second, record your interpretation. “The speaker repeats this appeal three times” is a different kind of statement from “the audience must have resisted the appeal”.
The second statement may become a useful hypothesis. It needs support, and alternatives should remain visible. Repetition could also reflect a formal convention or an editor’s arrangement.
Leave a trail back to the page
Record the edition, translator, page or section, and access link. When you paraphrase, keep the wording your own and retain the reference. When something is unclear, write a question instead of quietly smoothing it away.
For another layer of context, distinguish the age of a text from the age of its surviving copy. Careful reading often starts by keeping two apparently similar things apart.
Reference: Harvard Library, What is a Primary Source?