Post Hoc Ergo Propter Hoc Exercises (C1-C2)

⏱ Time: 07:30 📝 Questions: 15 📊 Level: C1, C2 📚 Type: Writing ⭐ XP: up to +22 (on pass)

Can you use Post Hoc Ergo Propter Hoc correctly in everyday English? These 15 practice questions for Level C1-C2 go beyond memorisation — they put writing concepts into realistic sentences and situations. Detailed explanations help you understand not just the what, but the why.

⏱ You have 07:30 to answer 15 questions. The timer only starts when you click Begin.

Q1  15
Q1 15

Question 1: Read the following passage: 'Ever since the city installed new streetlights, crime rates have dropped significantly. Clearly, better lighting is the sole reason crime has decreased.' Which term best describes the reasoning error demonstrated in this passage?

Question 1 options
The passage assumes that because crime decreased after the streetlights were installed, the streetlights must be the cause. This is the post hoc ergo propter hoc fallacy — assuming that temporal sequence implies causation.
Q2 15

Question 2: In a persuasive essay analysing logical fallacies, which sentence correctly completes this passage? 'The senator argued that unemployment fell because of her policy reforms. However, this reasoning is flawed; she commits the ___ fallacy by assuming that the chronological sequence of events proves a causal relationship.'

Question 2 options
The correct term is 'post hoc ergo propter hoc,' which specifically names the fallacy of assuming causation from temporal sequence. The other options name different fallacies that do not describe this reasoning pattern.
Q3 15

Question 3: The post hoc ergo propter hoc fallacy asserts that if one event follows another, the first event must have caused the second — regardless of whether any actual causal mechanism has been established.

Question 3 options
This is true. Post hoc ergo propter hoc literally translates to 'after this, therefore because of this,' and it is defined as the fallacy of assuming causation solely from temporal sequence without establishing a genuine causal link.
Q4 15

Question 4: Which of the following sentences correctly demonstrates the post hoc ergo propter hoc fallacy?

Question 4 options
The sentence about wearing a lucky hat and then passing the exam assumes causation from sequence — a textbook post hoc fallacy. The other options either describe genuine cause-and-effect, a correlation observation, or a different fallacy entirely.
Q5 15

Question 5: Match each logical fallacy term to its correct definition or description.

Question 5 options
Post hoc ergo propter hoc
Cum hoc ergo propter hoc
Non sequitur
Confounding variable
Assumes correlation proves causation
Conclusion does not follow from premises
Assumes sequence proves causation
Hidden factor that distorts apparent causation

Select an item on the left, then tap its match on the right.

Post hoc ergo propter hoc involves false causation from sequence; cum hoc ergo propter hoc involves false causation from correlation; a non sequitur is a conclusion that does not logically follow; and a confounding variable is an unaccounted factor that may explain an observed relationship.
Q6 15

Question 6: Which of the following sentences contains an error in the way it identifies or describes a logical fallacy?

Question 6 options
The sentence claiming post hoc ergo propter hoc involves assuming that two simultaneous events are causally linked is incorrect. Post hoc concerns sequential events, not simultaneous ones. Confusing simultaneous correlation with temporal sequence is a common error; the simultaneous version is cum hoc ergo propter hoc.
Q7 15

Question 7: Read the following passage from an academic essay: 'While some commentators insist that the new trade agreement caused the economic upturn, this claim deserves scrutiny. The recovery began months before the agreement took effect, and numerous other fiscal policies were implemented during the same period. ___, attributing the entire recovery to the trade agreement is a textbook example of post hoc reasoning.' Which transition word or phrase best fills the blank?

Question 7 options
'Consequently' is the best choice because it signals a logical conclusion drawn from the preceding evidence — that the timing and competing explanations undermine the causal claim. 'Nevertheless' and 'on the other hand' indicate contrast rather than conclusion, and 'for instance' introduces an example rather than a conclusion.
Q8 15

Question 8: The following sentence contains an error: 'The journalist committed the post-hoc-ergo-propter-hoc fallacy when she argued that the mayor's resignation lead to the city's budget crisis, despite the crisis predating his departure.' Which option correctly fixes the error?

Question 8 options
The error is the use of 'lead' (present tense or noun) where the past tense 'led' is required. The corrected sentence uses 'led to' appropriately. The other options either retain the original error, introduce a new spelling error ('resegnation'), or incorrectly change the verb to 'has lead' instead of 'has led.'
Q9 15

Question 9: Arrange the following structural elements in the correct order for an academic essay paragraph that identifies and refutes a post hoc ergo propter hoc argument.

Question 9 options
  • Offer an alternative explanation supported by stronger evidence
  • Identify the reasoning as the post hoc ergo propter hoc fallacy
  • Present the original claim that assumes causation from sequence
  • Provide counter-evidence that undermines the assumed causal link

Drag items or use arrows to arrange them in the correct order.

An effective refutation paragraph first presents the claim being critiqued, then identifies the specific fallacy, then provides counter-evidence, and finally offers an alternative explanation — following a logical progression from claim to critique to evidence to resolution.
Q10 15

Question 10: You are writing a formal academic paper on vaccine misinformation. You need to explain how a particular anti-vaccine argument relies on faulty reasoning. Which of the following is the most appropriate way to phrase your critique?

Question 10 options
The second option maintains an appropriately formal, measured academic register while precisely naming the fallacy and explaining its mechanism. The first is excessively colloquial ('dumb argument'), the third uses sarcasm ('genius logic'), and the fourth is too informal ('ridiculous').
Q11 15

Question 11: What is the key difference between post hoc ergo propter hoc and cum hoc ergo propter hoc as they are used in academic writing?

Question 11 options
Post hoc ergo propter hoc specifically involves the assumption that because event B followed event A, A caused B (sequential). Cum hoc ergo propter hoc assumes causation from events that merely occur together or correlate (simultaneous). The distinction lies in sequence versus co-occurrence.
Q12 15

Question 12: Which of the following is most appropriate for a formal letter to a public health official, warning about post hoc reasoning in policy decisions?

Question 12 options
The second option uses appropriately formal, diplomatic language suited to official correspondence, with precise terminology and a respectful tone. The first is condescending ('Perhaps you are unaware'), the third is too casual, and the fourth is overly emotional and lacks the measured register expected in formal correspondence.
Q13 15

Question 13: An argument can still commit the post hoc ergo propter hoc fallacy even if the assumed cause did, in fact, contribute to the outcome — the fallacy lies in the reasoning method, not necessarily in the truth of the conclusion.

Question 13 options
This is true. A fallacy is an error in reasoning, not necessarily an error in conclusion. Even if A did cause B, arguing that A caused B solely because B followed A is still fallacious reasoning. The conclusion may be accidentally correct, but the logical justification remains flawed.
Q14 15

Question 14: Read the following passage: 'The writer begins by narrating the personal anecdote of a farmer who switched fertiliser brands and subsequently experienced a bumper harvest. Rather than investigating soil conditions, weather patterns, or seed quality, the writer immediately declares the new fertiliser responsible for the yield increase.' What effect does the writer's use of post hoc reasoning create in this passage?

Question 14 options
By jumping from sequence to causation without examining alternative factors, the writer creates a misleadingly oversimplified causal narrative. This oversimplification gives the reader a false sense of certainty about the cause, which is the primary rhetorical effect of post hoc reasoning in persuasive contexts.
Q15 15

Question 15: The following sentence is weak and poorly constructed: 'The company sales went up after they changed the logo so the logo change is why sales went up which is what happened.' Which revision best improves this sentence while also correctly identifying the reasoning flaw?

Question 15 options
The best revision restructures the sentence for clarity and academic precision, explicitly names the post hoc fallacy, and introduces the possibility of alternative explanations. The other options either retain vague phrasing, introduce grammatical errors, or fail to identify the reasoning flaw accurately.