Phil 1102: Critical ThinkingPhil 1102: Critical Thinking

September 15, 2005Causal Reasoning &

Causation

So…So…

Anyone wuznuggle?

Causal FallaciesCausal Fallacies

• Confirming Evidence• Post Hoc ergo propter hoc• Failure to consider a common

cause.

When causation?When causation?

• A perhaps more appropriate question: when is causation perceived?

MichotteMichotte

• Causation?

MichotteMichotte

To Play with…To Play with…

Cartesian (and pre-Cartesian (and pre-modern) causationmodern) causation

• All causation happens instanteously when objects are touching. – Therefore, there is no causation at a

distance.– Therefore, there is no such thing as

space!

Hume’s ContentionHume’s Contention

• NO necessary connection, just repeated observation of one event following another.– We, through experience, develop laws

such as ‘Events of this type follow events of that type’.

– Events that fall under these laws are instances of causation.

– REGULARITY theory

RegularityRegularityWhat is necessary for the fan? Sufficient for the fan?

RegularityRegularityIs the cue necessary for the 8 ball falling into the corner pocket? Is it sufficient? What about the earthquake?

PartialPartialIs the cue ball partially responsible for the 8 ball? Is the non-existence of the earthquake also?

Partial InhibitoryPartial InhibitoryIs the switch’s being off a partial inhibitory?

Lewis’s Contention: Lewis’s Contention: CounterfactualCounterfactual

Some y is a cause of x iff if y had NOT happened, x wouldn’t have also

OverdeterminationOverdeterminationSome y is a cause of x iff if y had NOT happened, x wouldn’t have also

Anscombe’s contention: Anscombe’s contention: realismrealism

• Cause is productive, basic, real. Not analyzable in terms of ‘necessity’, ‘sufficiency’ or Lewis’ modality.

• Cause just is.

How to determine cause: How to determine cause: MillMill

• Method of agreement

How to determine cause: How to determine cause: MillMill

• Method of difference

Real case: Real case: SemmelweisSemmelweis

• Vienna general hospital. Death rates in maternity ward attended by Doctors from ‘childbed fever’.– 1844 = 8.2%, – 1845 = 6.8%– 1846 = 11.4%.

• Death rates in maternity ward attended by midwives:– 2.3%– 2.0%– 2.7%

Difference 1: the priest’s Difference 1: the priest’s approachapproach

If the priest’s approach was causing the higher death rates, then changing the route by which the priest entered in the doctor’s should reduce the death rate in the doctor’s ward.

Changing the route by which the priest entered did not reduce the death rate in the doctor’s ward

Therefore, The priest’s approach was not causing the higher death rate.

Difference 2: Cadaverous Difference 2: Cadaverous mattermatter

If cadaverous matter (or something similar) were not the cause of childbed fever, then it would be very unlikely that requiring doctor’s to wash their hands in chlorinated lime should have an effect on the death rate in the doctor’s ward.

Requiring doctor’s to wash their hands in chlorinated lime did have an effect on the death rate in the doctor’s ward

Therefore, it is very likely that cadaverous matter (or something similar) was the cause of childbed fever.

How to determine cause: How to determine cause: MillMill

• Method of concomitant variation

How to determine cause: How to determine cause: MillMill

• Method of residues

CorrelationCorrelationFinal Score & Post Test v Reading Report

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Causation?Causation?

• Reading is sufficient for doing well on the exam

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Causation?Causation?

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Causation?Causation?

• Reading is necessary but not sufficient for doing well on the exam

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• Reading is necessary but not sufficient for doing well on the exam

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