Ve Have Vays of Making You Talk, Part VI: Post Hoc Reasoning

In Part I ofthis post, I discussed why family members hate to discuss their chronicrepetitive ongoing interpersonal difficulties with each other(metacommunication), and the problems that usually ensue whenever theytry. 

Idiscussed the most common avoidance strategy - merely changing thesubject (#1) - and suggested effective countermoves to keep aconstructive conversation on track. In Part II, Idiscussed strategies #2 and #3, nitpicking andaccusations of overgeneralizing respectively. In Part III, Idiscussed strategy #4, blame shifting. In Part IV,strategy #5, fatalism.

This postis the second in a series about strategy #6, the use of irrationalarguments.  Descriptions of this strategy have been subdivided intoseveral posts because, in order to counter irrational arguments, one first hasto recognize them.  I will hold off describing strategies to counter the irrationalarguments until after I have describe some of the most common types.

Irrationalarguments are used in metacommunication to throw other people. The other individuals either becomes confused about, or unsure of the validity of, any point they aretrying to make or question they are trying to ask.  Fallacious argumentsare also frequently used to avoid divulging an individual's real motivesfor taking or having taken certain actions. 
The fallacy I would like to discuss in thispost is post hoc ergo propter hoc,which literally translated means "after this, therefore because ofthis." Under this fallacy, two events that occur in sequence are merely assumed to be causally related. That is,if event B follows event A, then an assumption is made that A caused B, even though many otherenvironmental events were also going on during the time between A and B that could havecaused B, eitherindividually or in some combination.

This sort of fallacy can be funny when it isobvious but difficult to detect when subtle. No one would believe a doctor whoclaims that headaches are caused by a deficiency in the body of aspirin, butthe debate rages on over whether the effects on assailants of por­nographicmovies caused them to become rapists.

I frequently see this fallacy used inarguments made by the anti-psychiatry crowd. If some psychiatric symptom developed by a patient occurred after he orshe either started or discontinued a drug, they argue that it simply must have been caused by themedication.  Well, sometimes it is, but oftenit is not.  The further removed in timefrom when the medication was started or discontinued, the less likely itbecomes that the drug had anything to do with the symptom. 

There are a very limited number of drug-inducedsymptoms that, once started, never go away, and those usually involve asituation in which a drug actually grossly damaged an organ.  Some dyes used in X-ray procedures, forexample, may physically damage the kidneys. Tardive dyskinesia, a long-termneurological problem in the central nervous system caused by antipsychoticmedication, is one obvious exception.

Withdrawal symptoms from addictivedrugs almost always go away after a relatively short period of time.

Withpatients in psychotherapy, the post hoc fallacy is most frequently seen with duringconjoint marital or family sessions. When spotted, such a fallacy may revealthe presence of a family myth.  A familymyth is a false belief that assists family members in suppressing thosethoughts, feelings, preferences, or behavior deemed to be unacceptable and inallowing one or more family members to continue playing a spe­cific role. Themyth may be believed by an individual, a sub­system of the family, or theentire family.

Familymyths may take the form of a causal explanation of a family member's be­haviorthat is not the true explanation. In order to be believ­able, the myth often makesuse of the post hoc ergo propter hoc fallacy. In such a myth, the belief in a causalconnection is based solely on a sequence of events that takes place in acertain period of of time. If the behavior to be explained begins after acertain event, the behavior is blamed on the event. As with other mechanismsused by people who are attempting to hide their true feelings and beliefs, theproposed cause often re­veals clues to the real cause, even though the proposedcause is meant to be a smokescreen.

Oneexample occurred in a family being seen under duress from a probation officer.A young teenager was caught shoplifting. He lived with his father and hissiblings. The mother ­had not only divorced the father but abandoned thefamily, entirely abdicating any family responsibility in order to pursue acareer. The father could rarely spend time with the boy because the firm thathe worked for was demanding more and more overtime. The father ­routinelyworked fourteen-hour days; he expressed disappointment· that the boy could nottake better care of himself without supervision.

The posthoc fallacy was expressed in the session following an incident in which the sonpicked a fight with another boy who was twice his size. The father theorizedthat the son had engaged in this rather dangerous activity because he had nothad a good night's sleep the night before the inci­dent - and was thereforeoverly irritable.

Thisseemed to me a rather odd explanation. When provoked, overly irritable peoplewill sometimes unthinkingly do or say things that they other­wise might keep tothemselves, but they seldom go out looking for trouble.

Thefather appeared to be attempting to veer away from any explanation of the boy'sodd behavior that might involve family dynamics, but he unwittingly revealed somethingabout himself. It was he, the father, not the son, who was irritable from lackof sleep.

I laterguessed that the boy's acting-out behavior was a feeble attempt to force thefather, who was utterly ex­hausted from working so much, to work less. The probationofficer had in fact required the father to be at home more in order tosupervise the misbehav­ing youngster. The boy was also bidding for moreattention, as many therapists would theorize, but I believed that he wasgenuinely concerned about his father’s mental health.

When Isuggested to the father that the boy was, at great per­sonal sacrifice,attempting to indirectly demonstrate his concern by forcing the father toinsist on more time off, the father never really bought it. However, soon Dad was spending more time home, and the patient stopped acting out. No causalconnection between my intervention and the boy’s subsequent im­provement wasever established. 


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