Logical Fallacies and Using
Statistics
What is a fallacy?
• Definition of fallacy: a misleading or unsound
argument. Any of various types of erroneous
reasoning that render arguments logically
unsound. (“erroneous” means “containing an
error”)
• See the handout for some common logical
fallacies
Why are logical fallacies tricky?
• Logical fallacies are tricky because they sound
good on the surface. Look at the example
fallacies provided on the handout. Which ones
look good on the surface?
Logical Fallacies in the Media
• Where do we see logical fallacies? In the
media? In advertisements?
• Logical fallacies are not always as easy to spot
as the ones that I have provided for you. Be a
savvy reader. Be aware of author biases and
of these patterns we have discussed. If you
see these fallacies in something you read,
question them.
How can you fix a logical fallacy?
• If you catch yourself or a peer in a logical fallacy, how
do you fix it?
• Moderate your language. One of the fundamental
rules of persuasive writing is “Don’t make claims you
can’t prove.” Also, if you make a sweeping
generalization and the audience can think of even ONE
example that disproves your generalization, you’ve lost
credibility with your reader.
• Give more specifics – this especially helps with proof
by too few examples, allness, and oversimplification
Fixing logical fallacies
• Allow for complexity – this definitely helps with
oversimplification and either/or reasoning
• Avoid common, over the top phrasing – say
things in a new way
• Build credibility – your own, and that of your
sources. Show yourself to be knowledgeable and
reasonable, and your sources to be trustworthy.
• Look at the big picture – think of various
people/issues who might be affected by your idea
and consider them before making blanket
statements.
Logos Review
• One of the ways you will be making your
argument is through the use of logos.
• Logos appeals to logic, reason, and “common
sense.”
• Arguments that use logos use often use statistics
and results of scientific studies and interpret
those statistics and results for the reader to show
how those facts support the claim.
Using Facts Effectively
• “You are entitled to your own opinion, but you
are not entitled to your own facts.” – U.S.
Senator Daniel Moynihan
• When you present factual findings (statistics or
study results) in your research paper, you are
going to need to do these things:
– Interpret the fact. Explain what it means to your
argument.
– Give your facts context.
– Make sure your facts are credible to the reader.
Your Sources May Have Done Some
Interpretation Already…
• In your research, you will find facts presented in two
different ways:
• Informative sources simply give you the facts and let
you draw your own conclusions. There are no beliefs
about the facts in informative sources, and it is up to
you to interpret the facts and explain why they fit your
claim.
• Persuasive sources will use facts in order to support a
claim. These types of sources will have beliefs about
what the facts mean and what should be done because
of them. These are the sources you can agree or
disagree with.
Informative/Persuasive: to Sum Up
• So, to sum up: if a fact is from an informative
source, it is up to YOU to interpret it.
• If a fact is from a persuasive source, you have
a choice.
– Use the fact without responding to your source’s
ideas about the fact.
– Quote the fact and the ideas, and then
agree/disagree with the ideas about the fact, not
the fact itself.
Logos and Statistics
• Many appeals to logos are based on research that has
statistical results.
• “An analysis by the Pew Research Center found that of
more than 67,000 news stories that appeared in
newspapers or on cable and network television, radio
and news websites, between February 2009 and
February 2010, 1.9 percent related in a significant way
to African Americans, 1.3 percent related to Latinos
and only .2 percent related to Asian Americans”
(Hannah).
• The author quotes this study in order to support his
argument that the media is not adequately
representing LBGTQ people of color.
Questions to Ask About
Statistics/Research
• Who conducted the research? Are they
credible?
• How recent is the research?
• How many individuals were included in the
study?
• What methods were used to conduct the
study? Were they fair and effective?
• If the statistics are interpreted/explained, who
is doing the interpretation?
There are three kinds
of lies: lies, damned
lies, and statistics.
- Mark Twain
Use Statistics Honestly
• Logos is a powerful tool for persuasion, but you
want to make sure that you are using the
research you encounter honestly.
• It is possible that legitimate, factual research
might be manipulated by an unethical writer.
A very over the top example:
• “California Community Colleges are doing a
terrible job. In a study of 2013 graduation
rates, the Chronicle for Higher Education
found that only 26.2% of students seeking a 2year degree finished within three years. This
means that barely more than one fourth of
students finish their degrees in a reasonable
amount of time. Taxpayers should be outraged
that their taxes are supporting institutions
with such low rates of success.”
Give Your Facts/Statistics Context
• The fact “only 26.2% of CA students finish their community
college degrees in three years” needs context.
• Which students were included in the study?
– “First time, full-time degree seeking students.”
– This means that students who took a break and then graduated
in a reasonable amount of time aren’t counted.
– Part time students who later became full time aren’t counted.
• 26.2% graduate in 3 years in California, but how does this
compare to other states?
– The national average is only 19.4%, so California is performing
BETTER than the national average in Community college degree
completion.
– Out of all 50 states, California has the 10th highest completion
rate (the highest is South Dakota, with 51.2% graduating in 3
years).
Questioning Facts: The Exception
• Remember how I said “you can’t argue with
facts”? There is one exception.
• If you find out that the research that provided a
statistic was not well done, you can question the
research.
• Point out a flaw in the study’s methods that you
discovered.
• Point out an unethical or unfair practice by the
study’s authors.
• Remember, though, you can only do these things
if you are ready to prove that the study is flawed.
A Problems to Watch out For
• Correlation is not causation (the verb
is “correlate”)
– Just because two things are happening at the same time, or
changing at the same rate, does not mean that they one is the
cause of the other.
• If you believe that two things are changing at the same
time or at the same rate because they are related, you
need to do much more to argue for the connection than
present statistics that say they are both changing.
• There are several amusing graphs about trends that prove
this point here, as well as a video that explains the issue in
more depth.
So what does all of this mean for my
research paper?
• Use facts and statistics wisely.
• When you are interpreting and explaining facts and
statistics, make sure you are doing so in a way that is
logical and fair.
– Let your audience know where the fact/statistic came
from, and argue for its credibility.
– Remember that correlation is not causation.
• When you are responding to your sources’
interpretations of facts, be sure that you are arguing
for or against the interpretation of the facts, and not
the facts themselves, unless you have proof that the
study is flawed.