Logical Fallacy Friday: False Cause and Slippery Slope

Interior photograph of the Troyes Cathedral The false cause fallacy comes in a couple of different Latin flavors: Cum Hoc Ergo Propter Hoc (with, therefore because of) and Post Hoc Ergo Propter Hoc (after, therefore because of). Both variants occur when one argues that because two events have occurred in time together or seem to have some kind of relationship, one must have caused the other. An example of the Cum Hoc fallacy would be something like:

Whenever it rains, I see people holding umbrellas. The fact that umbrellas and rain go together must mean that taking an umbrella outside causes rain.

I’ll let Martin Sheen and Alison Janney demonstrate the Post Hoc fallacy for you.

In this clip from the second episode of The West Wing, the Press Secretary (played by Janney) is arguing that the President’s public wisecracks are creating public relations problems. She ties a joke he made about golf to the fact that a group of pro golfers canceled their White House visit and a joke he made about big hats to the fact that Texas went Republican during the general election. The President reminds her that just because the canceled visit and the electoral loss happened after he told the jokes doesn’t mean that the jokes caused those events. The punch line is that they lost Texas when the President learned to speak Latin.

First frame:  "I used to think correlation implied causation."  Second frame:  "Then I took a statistics class.  Now I don't."  Third frame:  "Sounds like the class helped."  "Well, maybe."Cause and effect are usually complex relationships that can be mediated by any number of factors. Scientists talk a great deal about the difference between correlation and causation.  Two variables that appear to be related to one another may be causing one another, or they may both be caused by a third variable.  Last semester, I took a Sociology class for kicks.  The title of the class was “Religion, Health, and Mortality,” and in it we discussed the surprisingly vast body of research that shows a relationship between regular church attendance and physical and mental health, measured in both objective (blood pressure, cancer risk, etc.) and subjective (self-reported sense of well-being) terms.  It’s a rather shocking but difficult to deny statistical relationship that could have some disconcerting policy implications if one isn’t careful about how one understands the causal relationship between the two factors.  Is it really attendance at church that makes people healthier?  Should doctors and policy makers then be recommending that everyone get their ass into a pew on Sunday, whether religion is meaningful to them or not?  Is this somehow a scientific argument for the preferability or even necessity of religious lifestyles?

No, probably not.  The relationship between regular church attendance and health is not at all clear cut.  Most social scientists and epidemiologists (not to mention most respectable theologians) have written off the possibility that God intervenes and grants better health to those who follow his dictates by showing up to church.  Furthermore, it isn’t likely that attending church has some kind of direct and immediate effect on health by, say, lowering your blood pressure during a sermon.  So, rather than a causal relationship, we are probably talking about a mediating or moderating relationship between religion and health.  Some hypotheses suggest that churches provide forms of institutional and social support that people are unlikely to find in more secular contexts, a theory that seems to be supported by the fact that religion has the strongest relationship to health among poor older women of color.  Other research suggests that the religious make-up of a community plays a significant role in health care delivery.  Church members may also play a role in the lives of co-religionists by encouraging the use of preventative care as well as offering free services and referrals.  Furthermore, there is some indication (supported by studies of Buddhists and Christians) that an active spiritual life plays a role in relieving stress and moderating the effects of negative life events (such as sickness or injury).

So, the answer isn’t to get everyone in the world to start going to church. The answer is to do more research to figure out how we might translate the support systems provided by religion and spirituality in secular contexts.

My students often get slippery slope and false cause confused. They are related, but while the Post Hoc fallacy postulates that X caused Y because X and Y are related in time, the slippery slope fallacy is about prediction: X will cause Y and Z, because Y and Z are the natural outcomes of X. Usually, the intent is to cause alarm about the supposedly horrible consequences of something. I could show just about any clip of Glenn Beck or of Jon Steward making fun of Glenn Beck to demonstrate this one, but my favorite slippery slope example comes from the film Good Will Hunting. Transcript below. Enjoy.

Will Hunting (Matt Damon):  Why shouldn’t I work for the N.S.A.? That’s a tough one, but I’ll take a shot. Say I’m working at N.S.A. Somebody puts a code on my desk, something nobody else can break. Maybe I take a shot at it and maybe I break it. And I’m real happy with myself, ’cause I did my job well. But maybe that code was the location of some rebel army in North Africa or the Middle East. Once they have that location, they bomb the village where the rebels were hiding and fifteen hundred people I never met, never had no problem with, get killed. Now the politicians are sayin’, “Oh, send in the Marines to secure the area” ’cause they don’t give a shit. It won’t be their kid over there, gettin’ shot. Just like it wasn’t them when their number got called, ’cause they were pullin’ a tour in the National Guard. It’ll be some kid from Southie takin’ shrapnel in the ass. And he comes back to find that the plant he used to work at got exported to the country he just got back from. And the guy who put the shrapnel in his ass got his old job, ’cause he’ll work for fifteen cents a day and no bathroom breaks. Meanwhile, he realizes the only reason he was over there in the first place was so we could install a government that would sell us oil at a good price. And, of course, the oil companies used the skirmish over there to scare up domestic oil prices. A cute little ancillary benefit for them, but it ain’t helping my buddy at two-fifty a gallon. And they’re takin’ their sweet time bringin’ the oil back, of course, and maybe even took the liberty of hiring an alcoholic skipper who likes to drink martinis and fuckin’ play slalom with the icebergs, and it ain’t too long ’til he hits one, spills the oil and kills all the sea life in the North Atlantic. So now my buddy’s out of work and he can’t afford to drive, so he’s got to walk to the fuckin’ job interviews, which sucks ’cause the shrapnel in his ass is givin’ him chronic hemorrhoids. And meanwhile he’s starvin’, ’cause every time he tries to get a bite to eat, the only blue plate special they’re servin’ is North Atlantic scrod with Quaker State. So what did I think? I’m holdin’ out for somethin’ better. I figure fuck it, while I’m at it why not just shoot my buddy, take his job, give it to his sworn enemy, hike up gas prices, bomb a village, club a baby seal, hit the hash pipe and join the National Guard? I could be elected president.

Photo by Piotr Tysarczyk, Creative Commons Attribution-Share Alike 2.5 Generic

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