Cite a fact everyone knows and you look unserious. Fail to cite one they don't and you face a panel. The line is learnable.
It credits the people whose work you used. Leaving it out isn't an oversight, it reads as taking.
It shows your claims aren't invented. A cited claim is one the reader can go and check.
Over-cite common facts and you look like a beginner. Under-cite borrowed ideas and you risk your degree. This chapter is about telling the two apart.
Every claim in your draft belongs to one of two boxes. Common knowledge needs no citation; specialised knowledge always does. You make this call dozens of times an essay.
What an educated reader already knows and no one disputes.
Anything from someone's specific research, analysis, or argument.
| Claim | Verdict | Why |
|---|---|---|
| Seoul is the capital of South Korea. | Skip | Common; not in dispute. |
| Household debt hit 105% of GDP in 2024. | Cite | A specific figure, named body. |
| BTS has performed at the United Nations. | Skip | Widely reported, easily checked. |
| Pre-sleep screen light delays melatonin. | Cite | A mechanism someone established. |
| Korea has a low birth rate. | Skip | General, but the number (0.72) must be cited. |
| The 2016 protests drew over a million. | Cite | A contested count, attribute it. |
“Transformers underpin modern language models.” Cite it, or skip it?
A claim can be common in one field and specialised in another. When you can't tell, ask who is reading and what they already accept.
An extra citation costs the reader a second. An uncredited one can cost your degree. The asymmetry should settle most close calls.
Which style you cite in is set by discipline, APA for HASS & Business, IEEE for STEM, and MLA for literature (Workbook §11.4).
“My usual cafe keeps raising prices, so inflation must really be hurting students.”
“A 2024 Bank of Korea survey found dining-out prices up 5.2% year-on-year; for a student living on a fixed allowance, my cafe's third price rise this year is that statistic at the counter.”
If you catch yourself writing “I noticed” or “everyone knows,” the sentence is doing rhetoric. Frame it with evidence of another kind.
Two short exercises. The first tests the cite/skip call; the second matches each claim to the kind of evidence that proves it.
For each claim, decide: common knowledge (skip) or specialised (cite)?
| Claim | Skip | Cite |
|---|---|---|
| The 2002 World Cup was co-hosted by Korea and Japan. | ☐ | ☐ |
| Domestic-violence reports rose 18% from 2019 to 2023. | ☐ | ☐ |
| Han Kang won the Nobel Prize in Literature in 2024. | ☐ | ☐ |
| Korean adults sleep, on average, 6 h 41 min a night. | ☐ | ☐ |
Disagree on one? The tie-breaker is almost always who's reading, name the audience and decide again.
Which kind of evidence best supports each claim? Draw the lines.
A one-legged essay is all one kind of evidence. Aim for a mix, statistical, textual, and testimonial together.
Chapter 04, pages 19 to 21, including the “more calls” worked page and Exercises 4.1 to 4.3. Next, judge the sources themselves with the CRAAP test (Chapter 05).
Chapter 04 · Next, the CRAAP test for judging sources