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Reading Worksheet

The Logic of the Inexplicable

C1 Modals of Deduction: full range, present and past, with nuance Psychology and Strange Behaviour 25 minutes
Before You Read

Discuss these questions with a partner before you read.

  • Have you ever witnessed behaviour that you simply could not explain? What was it?
  • Do you think there is always a logical explanation for unusual human behaviour, or are some things genuinely inexplicable?
  • What is the difference between a psychologist and a detective? In what ways might their methods be similar?
  • Can you think of a time when you changed your mind about something after seeing new evidence?
Key Vocabulary
Word Definition Example
forensic (adj.) relating to the investigation of crime or unusual events using scientific or analytical methods The forensic psychologist was called in to analyse the suspect's behaviour.
rupture (n.) a sudden and dramatic break from a previous state or way of life The diagnosis caused a complete rupture in his relationship with work and family.
dissociation (n.) a psychological state in which the mind disconnects from thoughts, feelings, or surroundings Dissociation is sometimes the mind's way of protecting itself from extreme stress.
spontaneous (adj.) happening without prior planning, external cause, or conscious intent The crowd's applause was spontaneous — nobody had organised it.
probabilistically (adv.) based on likelihood or probability, rather than certainty Scientists reason probabilistically — they work with the most likely explanation, not absolute truth.
rigorous (adj.) extremely careful, thorough, and precise in thinking or method Rigorous analysis requires examining all possible explanations before drawing a conclusion.
Reading Text
Magazine Article ~335 words

The Logic of the Inexplicable

Dr Hana Novak has spent twenty years as a forensic psychologist, analysing behaviour that seems, on the surface, to defy explanation. In a recent interview, she discussed three cases that continue to challenge easy interpretation — and demonstrated how the language of deduction can illuminate what evidence alone cannot resolve.

Case 1 — The man who gave everything away: A 52-year-old businessman suddenly donated all his assets to strangers and moved to a remote village. "He must have experienced a significant psychological event," Dr Novak said. "This level of rupture from one's previous life is rarely spontaneous. He can't have acted entirely rationally — his behaviour was too sudden and absolute. He might have been responding to a medical diagnosis he hadn't disclosed. Or he could have simply reached a breaking point that had been building for years."

Case 2 — The woman who forgot her language: A bilingual professor woke one morning able to speak only her second language — English — and not her first, Hungarian. "This can't be purely linguistic," Dr Novak explained. "The brain doesn't simply erase a first language. It must be neurological or deeply psychological. It might be a form of dissociation triggered by trauma. She could have suppressed her first language as part of a broader emotional response to something she has not yet been able to articulate."

Case 3 — The child who drew maps of unknown places: A nine-year-old accurately sketched detailed street plans of a city in another country he had never visited. "He can't have learned this consciously — the detail is too precise for that. He must have accessed the information somehow, but the mechanism remains unclear. It might have been through a parent's photographs or stories he has no conscious memory of absorbing."

Dr Novak paused before her conclusion. "Deduction is not diagnosis," she said carefully. "When we say someone 'must have' experienced something, we are reasoning probabilistically, not conclusively. The most rigorous minds hold their deductions lightly — and remain willing to revise them."

Notice the Grammar

Read paragraphs 2 and 3. Find at least one example each of: must (present), can't (present), must have (past), and might have (past). For each one, identify what evidence Dr Novak is basing her deduction on. What does each modal tell you about her level of certainty?

1 Reading for Gist

Answer each question in a few words.

  1. Who is Dr Hana Novak, and what does she do?
  2. What is the central argument Dr Novak makes at the end of the article?
  3. What do the three cases have in common?
2 Reading for Detail

Write short answers based on the article.

  1. Why does Dr Novak say the businessman 'can't have acted entirely rationally'?
  2. What does Dr Novak propose as a possible explanation for the professor's language loss?
  3. What alternative explanation does Dr Novak offer for the child's knowledge of the city?
  4. What does Dr Novak mean when she says the most rigorous minds 'hold their deductions lightly'?  a) They refuse to make deductions without complete proof. b) They make deductions confidently but remain willing to revise them if new evidence emerges. c) They prefer not to discuss their reasoning with others. 
  5. In Case 2, Dr Novak says the situation 'must be neurological or deeply psychological'. What two possible categories of explanation does she identify?
3 True, False, or Not Given

Write T (True), F (False), or NG (Not Given) for each statement.

  1. Dr Novak has been working as a forensic psychologist for two decades.
  2. The businessman told his family about his plans before donating his assets.
  3. Dr Novak believes the professor's language loss is definitely caused by a neurological condition.
  4. The child had visited the city he drew maps of.
  5. Dr Novak draws a distinction between probabilistic reasoning and conclusive proof.
4 Vocabulary in Context

Answer these questions about words and phrases from the article.

  1. In paragraph 2, 'rupture' is used to describe the businessman's change of life. Which option best captures its meaning in this context?  a) A gradual transition to a calmer way of living. b) A complete and sudden break from his previous existence. c) A carefully planned decision to donate to charity. 
  2. Dr Novak says she analyses behaviour that seems to 'defy explanation'. What does 'defy explanation' mean? Use your own words.
  3. Find a word in paragraph 5 that means 'in a way based on probability rather than certainty'. 
  4. In paragraph 1, Dr Novak says deduction can 'illuminate what evidence alone cannot resolve'. What does this suggest about the relationship between evidence and deduction? Write your own interpretation.
5 Grammar in Context

Complete these activities about the full range of deduction modals.

  1. Find one example of each modal form in the article. Write the full sentence in each case. (a) must (present — certain positive deduction) (b) can't (present — certain negative deduction) (c) must have (past — certain positive deduction) (d) can't have (past — certain negative deduction) (e) might have or could have (past — uncertain deduction)
    a) must (present):  b) can't (present):  c) must have (past):  d) can't have (past):  e) might have / could have (past): 
  2. Dr Novak says: 'When we say someone must have experienced something, we are reasoning probabilistically, not conclusively.' What distinction is she making between 'must have' and certainty?
  3. Why does the article use 'can't be' (present) for Case 2 but 'can't have' (past) for Case 1? Explain the tense distinction.
  4. Rewrite each sentence as a deduction using the modal in brackets. (a) 'It is almost certain he had a significant psychological event.' (must have) → 'He ___ experienced a significant psychological event.' (b) 'It is impossible that the child learned this consciously.' (can't have) → 'He ___ learned this consciously.' (c) 'Perhaps she suppressed her first language.' (could have) → 'She ___ suppressed her first language.'
  5. Think of an unusual event or behaviour you have witnessed or read about. Write four sentences using the full range of deduction modals — at least two in the past form. Include a brief explanation of the evidence behind each deduction.
Personal Response — Discuss with a partner

Discuss with a partner. Share one idea with the class.

  1. Which of the three cases do you find most difficult to explain? What deductions would you make about it?
  2. Dr Novak says that even the most rigorous minds should 'hold their deductions lightly'. Do you agree? Can you think of a situation where holding a deduction too firmly could cause problems?
  3. Is there a distinction in your own language between expressing certainty and expressing high probability? How does it compare to English modals of deduction?

Answer Key

The Logic of the Inexplicable — C1 — Modals of Deduction: full range, present and past, with nuance

Exercise 1 — Reading for Gist

  1. She is a forensic psychologist who analyses unusual human behaviour.
  2. That deduction is not the same as diagnosis — 'must have' expresses probabilistic reasoning, not conclusive proof, and good thinkers hold their deductions lightly.
  3. They all involve unusual human behaviour that is difficult to explain with certainty.

Exercise 2 — Reading for Detail

  1. Because his behaviour was too sudden and absolute — a completely rational person would not act so dramatically without some powerful cause.
  2. A form of dissociation triggered by trauma, or a broader emotional suppression of her first language.
  3. He might have absorbed information through a parent's photographs or stories without consciously remembering it.
  4. b)
  5. Neurological (a brain-related cause) or deeply psychological (a mental/emotional cause).

Exercise 3 — True, False, or Not Given

  1. T — Paragraph 1 states: 'Dr Hana Novak has spent twenty years as a forensic psychologist.'
  2. NG — His family's reaction and whether he told anyone in advance are not mentioned in the article.
  3. F — She says it 'must be neurological or deeply psychological' and uses 'might be' and 'could have' — these are deductions, not a confirmed diagnosis.
  4. F — Paragraph 4 states he was 'a nine-year-old who had never visited' the city.
  5. T — Paragraph 5: 'we are reasoning probabilistically, not conclusively.'

Exercise 4 — Vocabulary in Context

  1. b)
  2. To resist or resist being explained — behaviour that normal reasoning cannot easily account for.
  3. probabilistically
  4. Evidence gives us facts, but facts alone do not always tell us what happened or why. Deduction — reasoning from evidence — can reveal likely explanations that the evidence does not directly state. Deduction illuminates because it adds inferential meaning to raw facts.

Exercise 5 — Grammar in Context

  1. Any matching sentences from the article. Examples: a) 'It must be neurological or deeply psychological.' b) 'This can't be purely linguistic.' c) 'He must have experienced a significant psychological event.' / 'He must have accessed the information somehow.' d) 'He can't have acted entirely rationally.' / 'He can't have learned this consciously.' e) 'He might have been responding to a medical diagnosis.' / 'He could have simply reached a breaking point.' / 'She could have suppressed her first language.' / 'It might have been through a parent's photographs.'
  2. 'Must have' expresses a high-probability deduction based on available evidence — the speaker is almost certain. But 'almost certain' is not the same as 'conclusively proven'. Dr Novak is making the epistemological point that deductive reasoning is probabilistic: it can be overturned by new evidence. 'Must have' closes off other possibilities with high confidence, but it does not eliminate them entirely.
  3. Case 2 describes the professor's current situation — the deduction is about what IS true now: 'This can't be purely linguistic' means it cannot currently be just a language issue. Case 1 describes events that already happened: 'He can't have acted entirely rationally' means that in the past, when he made his decision, rational thinking was not the governing factor. The present form deduces about the present; the past form deduces about a past event.
  4. (a) must have. (b) can't have. (c) could have (or might have).
  5. Answers will vary. Check: must / can't + be (present); must have / can't have / might have / could have + past participle (past). C1 respon

Notice the Grammar — suggested answers

Accept any five correct examples from the article that use the target grammar. Students should be able to explain why the grammar is used in each case.

Personal Response

Answers will vary. This section is for spoken discussion or short written response. There are no single correct answers.