Download Common Logical Fallacies

Common Logical Fallacies
Hasty generalization: Making assumptions about a whole group or range of cases based
on a sample that is inadequate (usually because it is atypical or just too small).
False cause (a.k.a. Post hoc): Assuming that because B comes after A, A caused B. Of
course, sometimes one event really does cause another one that comes later. But
sometimes two events that seem related in time aren’t really related as cause and event.
Red herring: Partway through an argument, the arguer goes off on a tangent, raising a
side issue that distracts the audience from what’s really at stake. Often, the arguer never
returns to the original issue.
False dichotomy: In false dichotomy, the arguer sets up the situation so it looks like
there are only two choices. The arguer then eliminates one of the choices, so it seems
that we are left with only one option. But often there are really many different options,
not just two.
Straw man: In the straw man fallacy, the arguer sets up a wimpy version of the
opponent’s position and tries to score points by knocking it down. But just as being able
to knock down a straw man, or a scarecrow, isn’t very impressive, defeating a watereddown version of your opponents’ argument isn’t very impressive either.
Missing the point: The premises of an argument do support a particular conclusion--but
not the conclusion that the arguer actually draws.
Appealing to authority: Often we add strength to our arguments by referring to
respected sources or authorities and explaining their positions on the issues we’re
discussing. If, however, we try to get readers to agree with us simply by impressing them
with a famous name or by appealing to a supposed authority who really isn’t much of an
expert, we commit the fallacy of appeal to authority.
Ad populum: There are several versions of the ad populum (“to the people”) fallacy, but
what they all have in common is that in them, the arguer takes advantage of the desire
most people have to be liked and to fit in with others and uses that desire to try to get
the audience to accept his or her argument. One of the most common versions is the
bandwagon fallacy, in which the arguer tries to convince the audience to do or believe
something because everyone else (supposedly) does.
Ad hominem: The ad hominem (“against the person”) fallacy focuses our attention on
people rather than on arguments or evidence. The conclusion is usually “You shouldn’t
believe So-and-So’s argument.” The reason for not believing So-and-So is that So-andSo is a bad person. In an ad hominem argument, the arguer attacks his or her opponent
instead of the opponent’s argument.
Source: “Fallacies,” UNC Writing Center, accessed March 18, 2008,
http://www.unc.edu/depts/wcweb/handouts/fallacies.html.
Professor Susanna Lee | History Department | North Carolina State University
Fallacies Activity:
What Caused the Civil War?
Analyze and evaluate the following arguments on Civil War causation:
The war was not caused by slavery. Jefferson Davis wrote that war was about southern
self-determination and that the “existence of African servitude was in no wise the cause
of the conflict.”
The Civil War was caused by slavery. All historians argue that the Civil War was caused
by slavery and dismiss the argument that the tariff caused the war.
Northerners waged the war in order to abolish the institution of slavery. Frederick
Douglass helped to enlist blacks into the Union army because he argued that the Civil
War was a war for freedom and equality. This fact was also recognized by Abraham
Lincoln as well when he noted in his second inaugural address that “All knew that this
interest was, somehow, the cause of the war.”
The express cause of the so-called civil war was not slavery. The real cause of the war
was the tariff issue. In March of 1861 the U.S. Congress was able to pass the Morrill
Tariff Act which raised the import tariff rate to an average of forty-one percent. The U.
S. Congress adopted a resolution early in the war that expressly stated that the war was
to preserve the union, period. Lincoln made the same statement early on. Lincoln
himself was a racist and believed that blacks were inferior and that free blacks had to be
colonized. Lincoln was also a tyrant who violated civil liberties in both the Union and
the Confederacy. How can Americans support such a racist tyrant?
People disagree about whether the Civil War was caused by internal improvements or
tariffs. Internal improvements never generated widespread opposition in the South.
Therefore, opposition to the tariff is a more compelling cause of the Civil War.
The cause of the Civil War was not slavery. Only about 4 percent of Southerners owned
slaves. Why would Confederate soldiers risk their lives to protect the property of people
who did? THE WAR WAS NOT ABOUT SLAVERY!!! If you have a problem with that,
then talk to H.K. Edgerton.
Everyone who is not ignorant knows that slavery caused the Civil War. David Duke
argues that the Civil War was about state’s rights. But Duke is a racist who used to be
leader of the Ku Klux Klan. Those who argue that slavery did not cause the war are racist
and believe that slaves were better off enslaved.
James McPherson argues that northern abolitionist sentiment caused the Civil War. In
focusing on this one factor, McPherson presents a reductive argument that does not
address the role of the political system or the economic system. His argument is too
simplistic and is therefore wrong.