You copy a striking sentence from a discussion of an ancient text. A week later, the words remain in your notebook, but the edition, passage number and reason for copying them have vanished. The note is now harder to check than it was to collect.
A source card is a compact way to keep the route back to a passage beside the claim you want to examine. It can be a paper card or a structured digital note; its usefulness depends on the information, not the format.
Give the passage an address
Record the work’s title as presented in the edition, the translator or editor, publication details and the passage locator. Include a page number where useful, but preserve section or paragraph numbers too if the edition supplies them.
For an online source, save the page URL and the date you consulted it. A screenshot can help recall the appearance, yet it should not be the only route back. If you are looking at a catalogue description rather than the text itself, label the card accordingly.
Keep three kinds of writing apart
Use separate spaces for a short exact quotation, your own paraphrase and the question you are asking. Make their boundaries visible. Otherwise a convenient summary can return months later disguised as the source’s wording.
An illustrative card might contain a paraphrase such as “the speaker contrasts two kinds of knowledge,” followed by “Does this distinction continue in the next section?” That question is an investigation to pursue, not evidence that the whole work follows the same scheme.
Record the step you have not taken
If you have only read a secondary author’s quotation, say so. If a translation points to another manuscript you have not examined, keep that reference as a lead. Do not list it as a source you personally checked.
This matters particularly when claims pass through several summaries. The card should show which link in that chain you actually consulted, rather than borrowing the apparent authority of the earliest work mentioned.
Before adding more cards, test one: can you find the passage again, distinguish the ancient text from editorial discussion, and explain your original question? Our note on asking questions of a primary source can guide the next reading. A small record that leads somewhere is more valuable than a large collection of sentences with nowhere to return.