The Role of Counterfactual Reasoning in Causal Judgements

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The Role of Counterfactual Reasoning in Causal
Judgements

• peter.menzies_at_mq.edu.au

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1. Introduction

• What is the connexion between counterfactuals and
  actual/token causation?
• One idea that has been much explored in
  philosophy and psychology is that the causal
  judgement c caused e is analytically tied to
  the counterfactual If c hadnt occurred, e
  wouldnt have occurred.
• The consensus among philosophers is that the
  concept of actual causation cant be reduced to
  counterfactuals. Pre-emption examples pose an
  insuperable obstacle to such a reduction.

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1. Introduction

• The consensus view among psychologists seems to
  be that counterfactual reasoning and causal
  reasoning are distinct forms of reasoning.
• Mandel and Lehman (1996), Mandel (2003), and
  Byrne (2005) cite experimental data that show
  that peoples causal judgements of the form c
  caused e are dissociated from counterfactual
  judgements of the form If c hadnt occurred, e
  wouldnt have occurred.
• The former seem to go with judgements about
  sufficient conditions and productive mechanisms,
  whereas the latter seem to go with judgements
  about enabling conditions and preventative
  mechanisms.

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1. Introduction

• My aim is to argue that philosophers and
  psychologists have been premature in dismissing
  the possibility that our causal judgements are
  analytically connected to counterfactual
  concepts.
• But we have to adopt a more subtle view of the
  connexion in order to able to accommodate the
  many examples cited as problematic for
  counterfactual theories.

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1. Introduction

• My plan of action
• Outline David Lewiss counterfactual theory.
  Explain some problems facing this theory,
  concentrating on the distinction between enabling
  conditions and causes, and the distinction
  between positive and negative causes.
• Examine two attempts to rescue the counterfactual
  theory from these problems
• a theory of Chris Hitchcock and Joshua Knobe
• a theory of James Woodward
• Outline a new theory I think is superior to both
  these theories.

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2. Lewiss Counterfactual Theory

• Lewis claims that causation can be analyzed in
  terms of counterfactual dependence defined as
• e counterfactually depends on c iff (i) if c
  were to occur, e would occur and (ii) if c
  werent to occur, e wouldnt occur.
• Counterfactuals are understood in terms of
  similarity relations between possible worlds.
• He imposes a constraint on the similarity
  relation which ensures that a counterfactual with
  a true antecedent and consquent is itself
  automatically true.

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2. Lewiss Counterfactual Theory

• This constraint means that his counterfactual
  dependence can be simplifed to
• An occurrent event e counterfactually depends
  on occurrent event c iff if c werent to occur,
  e wouldnt occur.
• Lewiss definitions of causal concepts
• c is a cause of e iff (i) c and e are wholly
  distinct events and (ii) there is a chain of
  counterfactual dependences from c to e.
• It follows that from this definition that
• If e counterfactually depends on a distinct
  event c, then c causes e.

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3. Problems for Lewiss Theory

• The theory glosses over the distinction between
  causes and enabling conditions.
• Example 1 Birth and Death.
• A man is born and much later dies in a car
  accident. If he hadnt been involved in the car
  accident, he wouldnt have died. So the car
  accident counts as a cause of his death. But if
  he hadnt been born, he wouldnt have died. So
  his birth counts as a cause too.
• The problem is exacerbated by the fact that the
  theory is supposed to cover omission and
  absences.
• Example 2 The Absence of Meteor Strike.
• Im writing this paper at my computer. If I had
  been struck by a meteor shower, I would not be
  writing this essay. So the failure of a meteor
  strike counts as a cause of my writing this
  essay.

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3. Problems for Lewiss Theory

• The theory has trouble distinguishing between
  genuine and spurious causes among omissions.
• Example 3 The Gardener and the Plant
• A gardener whose job it is to water a plant
  during hot weather fails to do so and the plant
  dies. If the gardener had watered the plant, it
  would have survived. So his failure counts as a
  cause of the plants death. But if the Queen had
  watered the plant, it would have survived as
  well. So the Queens failure counts as a cause
  too.

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3. Problems for Lewiss Theory

• Carolina Sartorio (2009) has noted the theory
  faces the Prince of Wales problem the problem of
  unwanted positive causes.
• Example 4 The Prince and the Plants Death
• The Queen has asked the Prince to water her pot
  plant in the afternoon. But his priorities are to
  eat oaten biscuits instead of watering the plant
  and so the plant dies. The Princes failure to
  water the plants caused the plants death.
• If we add the assumption that if the Prince had
  not eaten the oaten biscuits, he would have
  watered the plant, it turns out his eating oaten
  biscuits counts as a cause of the plants death.

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3. Problems for Lewiss Theory

• The problem of unwanted negative causes.
• Example 5 The Prince and the Stomach Ache
• The Prince eats oaten biscuits instead of
  watering the plant. He eats so many biscuits he
  gets a stomach ache. The Princes eating too many
  oaten biscuits was a cause of his stomach ache.
  But so too is his failure to water the plant if
  he had watered the plant instead of eating the
  biscuits, he would not have had the stomach ache.
• Indeed, any action precluded by the Princes
  eating the oaten biscuits (ie talking to the
  Duke, walking in the garden) will have a
  corresponding omission that counts as a cause.

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4. Hitchcock and Knobes Theory

• These problems indicate that a counterfactual of
  the form If c werent to occur, e wouldnt
  occur is not a sufficient condition for c is a
  cause of e.
• Lewis defended his theory against such
  counterexamples by appealing to Grices pragmatic
  theory of conversational implicature.
• It is literally true that any event or absence on
  which an effect causally depends is a cause of
  the effect. There are ever so many reasons why
  it might be inappropriate to say something true.
  It might be irrelevant to the conversation, it
  might convey a false hint, it might be known to
  all concerned

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4. Hitchcock and Knobes Theory

• Grices maxims are general principles of
  rationality applied to information exchange. Yet
  the principles that lie behind our judgements
  about the examples above seem to be particular to
  causal judgements.
• Is it possible to formulate a theory that
  captures the causation-specific principles that
  lie behind our judgements?
• Hitchcock and Knobe (2009) have formulated one
  such pragmatic theory that preserves the
  centrality of counterfactual dependence to the
  causal concept while explaining the selectivity
  of the causal concept.

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4. Hitchcock and Knobes Theory

• Their theory appeals to findings in the
  literature on psychological availability of
  counterfactual suppositions.
• One of the most robust findings in this
  literature is that people are disposed to
  entertain counterfactual hypotheses that undo the
  past by changing abnormal occurrences into normal
  ones, but seldom, if ever, do they mentally undo
  the past by changing normal occurrences into
  abnormal ones.
• Kahneman and Tversky (1982) gave subjects a story
  describing a fatal road accident in which a truck
  ran a red light and crashed into a passing car,
  killing its occupant, Mr Jones.

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4. Hitchcock and Knobes Theory

• Two versions of the story were constructed one
  in which Mr Jones left his home at the regular
  time but took an unusual route home, and the
  other in which he took the usual route home but
  left early to do some chores. In 80 of the
  responses, subjects indicated they mentally undid
  the accident by mutating the abnormal event and
  restoring it back to normality.
• In the first version of the story, subjects were
  inclined to entertain counterfactuals about what
  would have happened if Mr Jones had taken his
  usual route home. In the second version they were
  more inclined to entertain counterfactuals about
  what would have happened if Mr Jones had left
  work at his usual time.

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4. Hitchcock and Knobes Theory

• Hitchcock and Knobe use this finding to explain
  the selectivity of the causal concept.
• We readily accept a causal judgement c caused
  e when the counterfactual If c hadnt occurred,
  e would have occurred involves changing an
  abnormal occurrence into a normal one we rarely
  accept such a causal judgement when the
  counterfactual involves changing a normal
  occurrence into an abnormal one.
• They claim that we classify events in terms of
  single scale of normality that takes into account
  both statistical and prescriptive considerations.

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4. Hitchcock and Knobes Theory

• They presented subjects with a vignette in which
  a receptionist in the philosophy department keeps
  her desk stocked with pens. In contrast to
  administrative assistants who are permitted to
  take pens, faculty members are supposed to buy
  their own. One day an administrative assistant
  and Professor Smith walk past the receptionists
  desk and both take pens. Later that day, the
  receptionist needs to take a message but cant do
  so because there are no pens on her desk. When
  subjects are asked whether the administrative
  assistant or Professor Smith caused the problem,
  most subjects say that Professor Smith was the
  cause.
• Hitchcock and Knobes explanation
• If Professor Smith had not taken a pen, there
  would have been no problem involves a
  norm-restoring antecedent and so the
  corresponding causal judgement is acceptable.
• If the administrative assistant had not taken a
  pen, there would have been no problem involves
  replacing a normal occurrence with an abnormal or
  neutral occurrence and so the corresponding
  causal judgement is not acceptable.

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4. Hitchcock and Knobes Theory

• How does their theory fare in dealing with
  Problems 1 to 5?
• Problem 2 The Absence of Meteor
• The absence of the meteor strike caused me to
  write this paper is not acceptable because the
  corresponding counterfactual involves changing a
  normal event into an abnormal event.
• Problem 3 The Gardener and the Plant
• The gardeners failure to water the plants
  caused the pant to die is acceptable because the
  corresponding counterfactual involves a
  norm-restoring change.
• The Queens failure to water the plants caused
  the plant to die is not acceptable because the
  corresponding counterfactual doesnt involve a
  norm-restoring change.
• Problem 4 Prince of Wales Unwanted Positive
  Causes
• The Princes failure to water the plant caused
  its death is acceptable for the same reasons as
  above.
• The Princes eating oaten biscuits caused the
  plants death is unacceptable for the same
  reasons as above.

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4. Hitchcock and Knobes Theory

• Note that in all the examples, the
  counterfactuals corresponding to both causes and
  non-causes are true. In the Problem 3 The
  Gardener and the Plant, it is true both
• If the gardener had watered the plant, it would
  not have died. If the Queen had watered the
  plant, it would not have died.
• Hitchcock and Knobe say that the first
  counterfactual is more relevant than the
  second. But what is relevance?
• Relevant spring to mind readily. We need an
  account of the difference in causal status thats
  independent of whether something springs to mind
  readily.
• Relevant acceptable when explicitly
  entertained. Both counterfactuals seem to be
  acceptable.
• Relevant worth entertaining for practical
  purposes. From our perspective, neither
  counterfactual is practically significant.

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4. Hitchcock and Knobes Theory

• Another problem concerns the psychological
  findings that demonstrate a dissociation between
  causal judgements and reasoning about
  counterfactuals.
• Mandel (2003) made a study using the example of
  Mr Jones and the drunk driver.
• When asked for their counterfactual judgements,
  many subjects responded with judgements If Mr
  Jones hadnt taken the unusual route (or left at
  the unusual time), he would not have died.
• When asked for their causal judgements, most
  respond with the judgement The drunk driver
  caused Mr Joness death.
• Such studies cast doubt on the claim that the
  acceptability of the causal judgement c caused
  e goes hand-in-hand with the acceptability of
  If c hadnt occurred,e wouldnt have occurred.

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5. Woodwards Theory

• Like Hitchcock and Knobes theory, Woodwards
  theory attempts to explain the selectivity of
  causal judgements by augmenting Lewiss
  counterfactual theory with additional
  constraints.
• Like Lewis, he defines counterfactual dependence
  between states (including events, absences and
  omissions) in terms of these counterfactuals
• (i) If c were to occur, e would occur
  occurrence counterfactual
• (ii) If c werent to occur, e wouldnt occur
  non-occurrence counterfactual

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5. Woodwards Theory

• Woodward says that for the causal judgement c
  caused e to be acceptable, the
  occurrence-counterfactual (i) must be
  insensitive ie. there is a broad range of
  background conditions Bi that are not too
  improbable or far-fetched such that the
  following counterfactual is true
• If c were to occur in circumstances Bi
  different from the actual circumstances, then e
  would occur.
• Example of insensitive causation
• Shooting a person at close range with a large
  calibre bullet caused his death.
• Example of sensitive causation
• Lewiss writing a letter of recommendation for
  jobseeker X caused the death of a descendant of
  another jobseeker Y who was displaced by X.

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5. Woodwards Theory

• Woodwards theory links our readiness to accept a
  causal judgement to the degree of insensitivity
  of the occurrence- counterfactual (i).
• It explains some of our causal judgements about
  the earlier examples.
• Problem 2 The Absence of the Meteor Strike
• The absence of the meteor strike caused me to
  write this paper is not acceptable because the
  corresponding occurrence-counterfactual If there
  were no meteor, I would write this paper is not
  insensitive.
• Note that if I had been struck by a meteor, then
  the occurrence-counterfactual would be If there
  were a meteor strike, I would not write this
  paper, which is insensitive.

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5. Woodwards Theory

• However, Woodwards theory doesnt deal
  satisfactorily with example of Mr Jones and the
  Drunk Driver
• Mr Jones taking an unusual route home caused
  his death has a sensitive occurrence-counterfactu
  al an admissible variation is one in which drunk
  driver doesnt run the red light.
• The drunk drivers running the red light caused
  Mr Joness death also has a sensitive
  occurrence-counterfactual an admissible
  variation is one in which Mr Jones doesnt take
  the unusual route home.
• Accordingly, we should say that neither Mr
  Joness taking the unusual route home nor the
  drunk drivers running the red light caused Mr
  Jones death.

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5. Woodwards Theory

• Woodwards theory doesnt handle one half of the
  Prince of Wales problem problem of unwanted
  positive causes.
• The Princes failure to water the plant caused
  its death has an insensitive occurrence-counterfa
  ctual. So the Princes failure to water the plant
  counts as a cause of the plants death.
• But Princes eating oaten biscuits caused
  plants death also has an insensitive
  occurrence-counterfactual any variation on the
  actual circumstances which respects the
  stipulation that the Princes eating oaten
  biscuits precludes him from watering the plant
  will make the occurrence-counterfactual true.

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5. Woodwards Theory

• Its not clear that the theory has a satisfactory
  explanation of the problem of the professor and
  the administrative assistant.
• Is the occurrence-counterfactual If the
  professor were to take a pen, there would be a
  problem insensitive?
• There seem to be admissible variations in which
  the professor takes a pen but the administrative
  assistant does not, in which case there would be
  no problem.

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6. A New Theory

• Hitchcock and Knobes theory seems to be closer
  to the truth than Woodwards. I offer a theory
  that builds on and improves on the Hitchcock and
  Knobe theory.
• (a) Semantic rather than pragmatic theory.
• Hitchcock and Knobes theory is a pragmatic
  theory of relevance added onto a standard
  semantics of counterfactuals.
• I believe it is more fruitful to see our causal
  judgements about the various examples as
  reflecting their actual meaning.
• The theory Im presenting states that the
  meaning of a causal judgement involves a contrast
  between the actual course of events and a
  counterfactual course of events.

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6. A New Theory

• In this pair of contrasting situations, the
  actual situation contains an abnormal sequence of
  events which invites explanation or the
  ascription of responsibility.
• The actual situation deviates from the default
  situation by virtue of containing abnormal
  sequence of events. The paradigm case is a
  sequence of events initiated by an intentional
  action that is an exogenous interference in the
  normal course of events.

Counterfactual situation default course of events
Actual situation deviant course of events
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6. A New Theory

• (b) Salience of counterfactual possibilities
  rather relevance of counterfactuals
• The theory says that in considering a causal
  judgement we tacitly treat certain counterfactual
  possibilities as salient.
• We select a counterfactual possibility as a
  default to the actual situation in which a state
  c obtains in such a manner that it meets the
  following condition the counterfactual
  possibility must be a norm-conforming situation
  in which c does not obtain.
• As in Hitchcock and Knobes theory, the norms
  include statistical norms, social and ethical
  norms, and norms of proper functioning. I also
  assume that in a given context we judge
  situations to be more or less normal in terms of
  single scale.

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6. A New Theory

• While this theory appeals to counterfactual
  possibilities, it avoids the use of
  counterfactuals.
• As we saw earlier, in most of the examples, both
  the causes and non-causes have true
  non-occurrence counterfactuals. Eg
• If the gardener had watered the plant, it would
  not have died.
• If the Queen had watered the plant, it would not
  have died.
• Hitchcock and Knobes theory then has to invoke
  the notion of relevance to sort out the causes
  from the non-causes.
• It is best simply to miss out the distracting
  detour through counterfactuals.

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6. A New Theory

• (c) Causation as difference-making without
  counterfactuals.
• Hitchcock and Knobes theory appeals to
  non-occurrence counterfactuals to spell out the
  idea that causation is linked to
  difference-making. The present theory spells out
  this idea out more directly
• c is a (difference-making) cause e is true
  iff there is a contrast pair ltA,Cgt, where A is
  the actual situation and C is an appropriate
  default counterfactual situation such that c
  and e are present in A but absent in C.

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6. A New Theory

• (d) Better explanation of causal judgements.
• The theory explains our causal judgements about
  the examples roughly in the same way as Hitchcock
  and Knobes theory.
• The Absence of the Meteor Strike
• The absence of a meteor strike was a cause of
  my writing this paper is false because there is
  no contrast pair with an appropriate default
  counterfactual situation (any situation in which
  I am struck by a meteor is abnormal)
• Prince of Wales Unwanted Positive Causes
• The Princes failure to water the plant was a
  cause of its death is true because there is
  contrast pair with a default counterfactual
  situation (where the Prince meets his obligation)
  which meets the difference-making condition.
• The Princes eating oaten biscuits was a cause
  of the plants death is false because there is a
  contrast pair with a salient default
  counterfactual situation (where he meets his
  obligation) but it doesnt meet the
  difference-making condition.

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6. A New Theory

• The present theory is consistent with the
  psychological studies showing that causal
  judgements are dissociated from judgements about
  counterfactuals. The present theory employs
  counterfactual possibilities but not
  counterfactuals.
• Nonetheless, it strikes me that Mandels use of
  the example about Mr Jones and drunk driver
  doesnt bear out this dissociation very well.
• In this example, Mr Joness taking an unusual
  route and the drunk drivers running the red
  light were causes of his death. In each case
  there is an appropriate contrast pair meeting the
  difference-making condition.

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6. A New Theory

• (e) Better Rationale for Causal Concept
• Why do we have the concept of actual causation
  (in addition to the concept of objective causal
  structure)?
• Hitchcock and Knobe claim that its purpose lies
  in its connexion with norms through its
  connexion with non-occurrence counterfactuals,
  the concept enables us to focus on what must be
  done to bring events into conformity with certain
  norms. In short, the concept of actual causation
  enables us to pick out appropriate targets for
  intervention.
• In contrast, the concept of actual causation has
  a very easy-to-understand rationale according to
  the present theory. The concept has its home in
  our practices of explanation and the attribution
  of responsibility. When an occurrence violates a
  statistical norm, we want to have an explanation
  of it. When it violates a prescription norm, we
  want to attribute responsibility for it to
  someone. A cause that makes a difference is
  perfectly suited to meet these functions.