Common mistakes · TOK · 8 min read
12 TOK essay mistakes that pull your mark down, and how to fix each one
Twelve common mistakes, each with a losing version, a better version and the habit that prevents it.
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TOK essays usually lose marks through a small set of repeated habits rather than a misunderstanding of TOK: answering a question near the title instead of the title itself, using imaginary examples, setting up counterclaims that are easy to knock down, and ending with a summary instead of a judgement. Below are twelve of these mistakes, each with a version that loses the examiner's confidence and a version that earns it.
The titles quoted below are invented by us in the style of prescribed titles; none is from a real session. For the full method, start with the TOK essay guide.
Mistakes with the title
1. Answering a different question
The essay is marked on how well it explores the title it was set. The most expensive mistake is drifting to an easier, nearby question, often one the student prepared in class.
Off the titleTitle: "Is the knowledge we gain from experts more useful than the knowledge we gain from experience?" The essay discusses whether experts are reliable and whether experts can be biased. "Useful" never appears after the introduction.
On the titleThe essay keeps the key comparison in view: useful for what, and compared with experience. Each section ends by saying which kind of knowledge served better in that example, and why.
Habit: after each body paragraph, write the title's key word in the margin and ask whether the paragraph moved the answer on.
2. Ignoring the qualifiers and instructions
Words like always, only, more, to what extent and the instruction about areas of knowledge are part of the question. Dropping them changes it.
Loses focusTitle: "Must knowledge always be justified by evidence?" The essay shows that evidence matters in the natural sciences and stops there.
Uses the qualifierThe essay accepts that evidence usually matters, then hunts for the cases that break "always": in mathematics, a theorem is justified by proof rather than observation; in the arts, a judgement about a painting may rest on trained perception. The answer is built on those exceptions.
3. Never questioning the title's assumptions
Many titles hide an assumption: that two things can be cleanly separated, ranked, or measured. Accepting it without comment leaves the most interesting paragraph unwritten.
Accepts the frameTitle: "Is knowledge produced by individuals more reliable than knowledge produced by groups?" Two sections: individuals, then groups.
Tests the frameThe essay notes that the line is blurred: Andrew Wiles worked largely alone on Fermat's Last Theorem, yet his 1993 proof contained a gap that was only found and repaired through other mathematicians' scrutiny before publication in 1995. If individual knowledge needs group checking to become reliable, the title's contrast is less sharp than it looks.
4. Over-defining terms with a dictionary
Dictionary definitions take words, settle nothing, and suggest the meaning is fixed when TOK is usually about how it isn't.
Dictionary"The dictionary defines evidence as 'the available body of facts or information indicating whether a belief or proposition is true or valid.'"
Working definition"In this essay, evidence means whatever a discipline accepts as a reason to believe a claim: measurements in physics, documents and artefacts in history. Part of the question is whether those count as the same kind of thing."
Remember that quotations count towards the 1,600 words, so a quoted definition costs you twice.
Mistakes with examples
5. Hypothetical examples
"Imagine a scientist who…" is not evidence of anything; you can imagine whatever outcome your argument needs. Examiners want real cases with names, dates and places.
Hypothetical"For example, a scientist might propose a theory that goes against the consensus and be ignored, even though they turn out to be right."
Real and specific"In the early 1980s, Barry Marshall and Robin Warren argued that most stomach ulcers were caused by the bacterium Helicobacter pylori, not stress. The idea met strong resistance; in 1984 Marshall drank a culture of the bacterium and developed gastritis. The pair received the Nobel Prize in Physiology or Medicine in 2005."
6. The examples everyone else uses
Some examples turn up so often that they tell the examiner you used the first case in your class notes or textbook: Semmelweis and handwashing, Galileo and the Church, Pluto losing planet status in 2006, "people used to think the Earth was flat". They're not wrong, but they're rarely analysed in any depth because everyone knows the one-line version.
Familiar"Galileo was punished by the Church for saying the Earth moves round the Sun, which shows authority can suppress knowledge."
Fresh"In 2012 archaeologists found a skeleton under a car park in Leicester. The identification as Richard III rested on several independent strands: the site matched historical records of the friary where he was buried, the skeleton had severe scoliosis, radiocarbon dating fitted, and in 2013 its mitochondrial DNA matched living descendants of his sister. History here behaved like a natural science, building confidence by agreement between independent methods."
Habit: look first in your own subjects. Your Biology IA, a source from History, a theorem from your Maths course. You know these well enough to analyse.
7. Telling the story instead of analysing it
A real example can still be wasted if it gets 150 words of narrative and one sentence of analysis. The example is evidence; the analysis is the argument.
NarrativeA full paragraph on how Banksy's Girl with Balloon shredded itself at a Sotheby's auction in 2018, ending: "This shows art can be surprising."
AnalysisTwo sentences of facts (the work partly shredded itself moments after being sold, and was re-titled Love is in the Bin), then the knowledge question: if destroying the work changed its meaning and arguably its value, who decides what an artwork is: the artist, the market or the audience?
8. Describing areas of knowledge instead of analysing them
The examiner knows what history and the natural sciences are. Paragraphs that explain them are word count spent on nothing.
Description"History is the study of past events. Historians use primary and secondary sources to find out what happened. The natural sciences use the scientific method, which involves hypotheses and experiments."
Analysis"Unlike a chemist, a historian cannot rerun the past; the only check on an interpretation is other evidence from the same past, which is why new evidence, like the Leicester DNA match, can settle a question that centuries of guesswork could not."
Mistakes with the argument
9. No counterclaim, or a straw man
A counterclaim that is obviously weak (a straw man) is barely better than none. The examiner is looking for the strongest objection to your position and an honest assessment of how much damage it does.
Straw man"Some people might say that mathematical knowledge is uncertain, but this is wrong because maths is based on proof."
Real counterclaim"Yet proof is only as certain as our ability to check it. The 1976 proof of the four colour theorem by Kenneth Appel and Wolfgang Haken relied on a computer checking well over a thousand cases, far more than anyone could verify by hand. Accepting it meant trusting the program, a kind of trust that looks closer to the natural sciences than to traditional proof."
10. An unsupported "it depends"
"It depends on the area of knowledge" is where a judgement should begin, not where it ends. Say what it depends on and which way it goes.
Vague"Whether experts should be trusted depends on the situation and the area of knowledge."
Specified"Trust in experts is most justified where their claims can later be tested by people outside the field, as with a forecast that turns out right or wrong, and least justified where only other experts can assess them, as with the attribution of an old painting. The dependency is checkability, not the area of knowledge itself."
11. Wasting the word count
Examiners stop reading at 1,600 words, so every wasted sentence pushes your conclusion closer to the cut-off. The usual leaks:
- A 250-word introduction that restates the title, gives the history of the topic and lists what each section will do. Aim for about 150 words: key terms, knowledge question, your position, your areas of knowledge.
- Long quotations (they count).
- Narrative paragraphs about examples (see mistake 7).
- Saying the same point in each section's closing sentence and again in the conclusion.
Habit: on your last draft, highlight every sentence that only describes. If it isn't needed for the reader to follow the analysis, cut it.
12. A conclusion that summarises instead of judging
The conclusion should answer the title, say which part of your argument carried most weight, and admit the limits of the answer.
Summary"In conclusion, this essay has looked at mathematics and history. In mathematics, knowledge is certain because of proof, but proofs can be hard to check. In history, knowledge is less certain. Therefore it depends on the area of knowledge."
Judgement"Proof gives mathematics a kind of certainty history can't have, but the four colour theorem shows that certainty rests on trust in whoever, or whatever, does the checking. The gap between the two areas is therefore one of degree: both rely on a community accepting a method. The weakest point in this answer is that it rests on unusual proofs; for most theorems a student can check, the gap may be wider."
A ten-minute check before you submit
- Is the title copied exactly, and does every section answer it?
- Does every example have a name, a date or a place?
- Is any example also in your class notes or textbook word for word? If so, can you add something new?
- Does each counterclaim come with its own real example?
- Does the conclusion give a judgement in its first sentence?
- Is the word count 1,600 or under, with quotations included?
The same habits matter in the exhibition, and many carry over to the Extended Essay's discussion and evaluation. See the TOK exhibition guide and the Extended Essay guide. If you've been tempted to have an AI tool draft or rewrite paragraphs, read AI for IB first: undeclared AI text in an assessed essay is academic misconduct.
Questions students ask
How many examples should a TOK essay have?
There's no required number. A sensible pattern is one well-analysed example per claim and per counterclaim, which usually means four to six in total. Two analysed examples beat five listed ones.
Can I use examples from my own IB subjects?
Yes, and they're often the best ones, because you understand them well enough to analyse them. A specific result from your Chemistry practical or a source you studied in History is far better than a hypothetical.
Are famous examples like Galileo or Semmelweis banned?
No. They're just used so often that they rarely tell the examiner anything new. If you use one, make sure you know the details and use it to make a point the usual retelling doesn't.
Is it a mistake to agree with the title?
No. You can agree, disagree or agree under conditions. The mistake is taking a position without testing it against a real counterclaim.