False Cause
KSU   -   English 1101/55 & 57   -   Mr. Hagin   -   Fall 2002   -   Revised: 27 November 2002


False Cause – identifying an improper or unrelated cause for an observed effect.

Writers often state reasons for the occurrence of events or circumstances.  However, these reasons must have a basis on the facts, not opinions.  People often make up explanations for things that they do not understand themselves. The Latin phrase post hoc, ergo propter hoc means “after this, therefore because of this.”  Just because one action or event seems to influence another, the first does not necessarily cause the second to occur.

Often, coincidence is the true explanation, meaning that the two events are unrelated, and any attempt to connect these events would be rash and invalid without clear proof.  This fallacy only shows up in common, every-day examples from popular culture, advertising, campaign rhetoric, etc.


We must draw conclusions based on our knowledge of the world and how it operates.  For instance, when dark clouds roll across the horizon, we can conclude that it will rain very soon.  We reason that the cause of rain (the clouds) will create an effect (rain) because our experience and knowledge develop this pattern.

You can also reason from effect to cause: if the ground is wet (effect) then it must have rained the night before (cause).  But not every cloud is a rain-making cloud.  The presence of just any cloud does not forecast rain, but the presence of a cumulo-nimbus cloud (tall dark clouds) most certainly does.  In order to accurately predict causes and effects, we must be able to understand the complexities of the world around us.  Assuming (instead of knowing) that one event must have followed another can create a cause-effect fallacy.


Students posing as super sleuths conclude the following: “Two fellow classmates got sick right after science class; therefore, science class must have made them sick.”

Although the possibility must be examined, upon further investigation we can conclude that other causes might have contributed to the illnesses: the food the students ate could have been bad, they might have been exposed to a virus, or a chemical in the lab could have been released into the air, etc.  The “class” itself did not cause any illness; its use in this sentence suggests that it is also an example of loaded language, overgeneralization, or sarcasm.  In reality, we probably would not really know the cause of these students’ illnesses immediately, so guessing only leads to gossip and hysteria.  This, in turn, would generate another logical fallacy – the non sequitur – that incorrectly  suggests that the sequence of attending science class (and then leaving it) will get one sick.


Hopefully, your doctor doesn’t tell you this: “Everyone forgets things because there is only so much room in the brain.”

Although the brain's capacity is limited, a quick check of the facts reveals that humans only use about 10% of their total brain capacity, making the above example an illogical argument.  This writer is speculating rather than checking the known facts.  The cause of the forgetfulness must be attributed to other reasons, such as poor study habits, distraction, or procrastination.  Notice again that a lack of knowledge about how the world works (in this case, human biology) causes these fallacies to be committed.  This foolish statement about brain capacity also falls under the invincible ignorance fallacy.


A superstitious person might say: “A black cat crossed Joe's path yesterday, and he died last night from the bad luck.”

Many of our superstitions stem from use of the false cause fallacy.  Somewhere back in history, one man must have had bad luck coincidentally after seeing a black cat walk in front of him.  Animals often were used as scapegoats for the unpleasant happenings in people’s lives.  The same bad luck apparently happened to the guy who broke a mirror and walked under a ladder.

William Shakespeare’s tragedy Macbeth told the story of a Scottish king who killed his way up to the throne.  For over four hundred years, actors have refused to utter the title of the play for fear that it causes bad luck.  Instead of saying “Macbeth,” they refer to the play in euphemism: “The Scottish Play.”  If an actor accidentally utters the title, he has to perform a series of incantations to ward off the spell (including spinning in circles, knocking on hickory doors, and repeating an old witches’ chant).

Superstitions, such as the example above, also typically utilize the non sequitur fallacy, which is a type of false cause fallacy.