reproduced from

This post is Part 5 of my continuing series, How to Talk to Relatives about Family Dysfunction. They posts provide win-win strategies for overcoming chronic repetitive problematic interactions between potentially loving family members. 

In Part I, I discussed why family members hate to discuss their chronic interpersonal difficulties with each other (metacommunication), and what usually happens when they try. I discussed the most common avoidance strategy — merely changing the subject (strategy #1)—as well as suggesting effective countermoves to keep a constructive conversation on track. In Part 2, I discussed the avoidance strategies of nitpicking (#2) and accusations of over-generalizing (#3). In Part 3, I discussed attempts to change the subject by getting into the blame game, and taking a shifting stance as to who exactly is to blame for a given family problem (#4). In Part IV, I discussed strategy #5, the use of fatalism to derail metacommunication., and strategy #6, the use of non-sequiturs.

The goal of metacommunication is effective and empathic problem solving. I again repeat the strong caution: Please be advised that sticking to the counterstrategies that I describe may be extremely difficult, so the services of a therapist who knows about these patterns are often necessary. For families in which violence and/or shattering invalidation of people who speak up is common, a therapist who can coach you in effectively employing the techniques is essential. Also, the advice in my posts is designed for adults dealing with other adults. It is not meant for metacommunciation with children and teens.

The strategy I would like to discuss in this post is the use of the logical fallacy, post hoc ergo propter hoc, which literally translated means "after this, therefore because of this." Under this fallacy, two events that occur in sequence are merely assumed to be causally related. That is, if event follows event A, then an assumption is made that caused B, even though many other environmental events were also going on during the time between A and that could have caused B, either individually or in some combination.

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

People argue, for another example, that marijuana is a gateway drug to heroin. It is also true that most heroin users drank Coca-Cola before moving on to heroin, so I guess soft drinks are gateway drugs as well. In this case, the fallacy is known as post coke ergo propter coke.

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

There are indeed a very limited number of drug-induced symptoms that, once started, never go away, and those usually involve a situation in which a drug actually grossly damages an organ.  Some dyes used in X-ray procedures, for example, may physically damage the kidneys. Tardive dyskinesia, a long-term neurological problem in the central nervous system caused by antipsychotic medication, is another obvious example. Withdrawal symptoms from addictive drugs almost always go away after a relatively short period of time.

With patients in psychotherapy, the post hoc fallacy is most frequently seen during conjoint marital or family sessions. When spotted, such a fallacy may reveal the presence of a family myth. A family myth is a false belief that assists family members in suppressing those thoughts, feelings, preferences, or behavior deemed to be unacceptable and in allowing one or more family members to continue playing a spe­cific role. The myth may be believed by an individual, a sub­system of the family, or the entire family.

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

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

The post hoc fallacy was expressed in the session following an incident in which the son picked a fight with another boy who was twice his size. The father theorized that the son had engaged in this rather dangerous activity because he had not had a good night's sleep the night before the inci­dent - and was therefore overly irritable.

This seemed to me a rather odd explanation. When provoked, overly irritable people will sometimes unthinkingly do or say things that they other­wise might keep to themselves, but they seldom go out looking for trouble.

The father appeared to be attempting to veer away from any explanation of the boy's odd behavior that might involve family dynamics, but he unwittingly revealed something about himself. It was he, the father, not the son, who was irritable from lack of sleep.

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

When I suggested to the father that the boy was, at great per­sonal sacrifice, attempting to indirectly demonstrate his concern by forcing the father to insist on more time off, the father never really bought it. However, soon Dad was spending more time home, and the child stopped acting out. No causal connection between my intervention and the boy’s subsequent im­provement was ever established.

In family metacommunication, family member #1 may try to deter family member #2 from discussing family dynamics by using a post hoc argument to invalidate or summarily dismiss a theory offered up by family member #2 about something going on in the family. 

In terms of how to counter this sort of strategy, I will defer a description of the countermoves until after the post in this series that finishes up with the use of logical fallacies, because the strategy of countering logical fallacies is the same for all of them and therefore will also apply to the last three fallacies I will be discussing in the upcoming posts: begging the question, arguing from worst case scenarios, and ad hominem or personal attacks. In that post, I will also discuss how to counter the game without end.

You are reading

A Matter of Personality

Parents Cut Off by Adult Children: Clueless? Part 2

Some adult children think their parents secretly need a break from parenting.

Psychodynamic Vs. Cognitive Therapy: Defense Mechanisms

Irrational cognitions and defense mechanisms may share a common purpose.

Ambiguous Family Communication: Explanation, or Description?

More tips for getting reluctant family members to tell you the whole truth.