Logical
Fallacies
What is a Fallacy?
• According to Webster’s Dictionary, a
fallacy is an error in thinking or reasoning.
• It’s an argument that does not conform to
the rules of logic, but appears to make
sense.
Fallacies
• Bad arguments are called fallacies.
• There are many fallacies of which many
people think that they are good
arguments.
• Fallacies usually follow certain patterns, so
there are several categories of common
fallacies.
• You can see fallacies around you all the
time once you recognize these patterns.
You can’t get away from Fallacies!
• Fallacies are all around you…
• Advertisements in magazines, on T.V., on
billboards all contain fallacies!
• Can you think of a place where there are
NO advertisements?
– Probably not! That’s because advertising is
impossible to escape and ad-free zones rarely
exist.
Impact of Fallacies
• What might be the impact of being told
that we are not pretty, handsome, rich,
clean, or good enough?
• What does the casual acceptance of
surrounding ourselves with fallacies say
about us?
One kind of Fallacy
is called Red Herring
Definition: Red Herring is a stinky fish that could
distract even the best of blood hounds from what
they are searching for. Red Herring means that
you are distracting your audience from the main
point by bringing up something else unconnected
with the logic of the argument.
Example:
You should take my side on this weight issue
because I played basketball in the Olympics
and trained with Hungary’s national champion
Fallacy:
Emotionally Loaded Terms
Definition: Using emotionally charged words to
distract the reader from the real argument (a type
of red herring).
Example:
You slowly poison your children
when you feed them fast food.
Fallacy:
Ad Hominem (This means
against humans)
Definition: Attacking the person instead of their
arguments (another type of red herring).
Example:
The reason why the Bush administration’s
plan for battling obesity In America is wrong is
because Bush is stupid.
Fallacy:
Faulty Cause and Effect
Definition: Saying that because one event
precedes another in time, it causes a second
event. Also known as “correlation does not equal
causation.”
Example:
Because children are using cell phones more
and more and the obesity rate is rising at the
same time, cell phones cause obesity.
Fallacy:
Either/Or Reasoning
Definition: An author limits the solution to two
possible choices, instead of allowing for other
possibilities.
Example:
Parents should either let their children get fat
by eating fast food all the time or never let
them eat fast food. The choice is obvious.
Fallacy:
Hasty Generalization
Definition: Also known as jumping to conclusions
Example:
A recent study showed that kids who are getting more
obese also happen, on average, to watch 4 hours of
TV a day. Therefore, to solve the problem, no children
should watch TV.
• Hasty generalization (or jumping to
conclusions) draws a conclusion about a
population based on a small sample.
– Example: I’ve met two people in Nicaragua
so far, and they were both nice to me. So, all
people I will meet in Nicaragua will be nice to
me.
Fallacy: Oversimplification
Definition: When an author proposes an overly easy
solution to a difficult or complex problem.
Example:
The answer to childhood obesity is to
teach kids to “just say no” to bad food.
Fallacy: Straw Man
Definition: Constructing a feeble version of your
opponents argument and destroying it, indicating that
your position is much stronger.
Example:
Those who say that kids should go on diets
are simply telling us to send our kids to
Weight Watchers, which not everyone can
afford. My plan for exercise promotion is
better because fresh air and walking is free.
Types of Fallacies: Appeal to Emotions
• Appeal to emotions manipulates people’s emotions in
order to get their attention away from an important
issue.
• You commit the fallacy of appeal to emotions when
someone’s appeal to you to accept their claim is
accepted merely because the appeal arouses your
feelings or anger, fear, grief, love, outrage, pity, pride,
sexuality, sympathy, relief, and so forth.
Types of Fallacies: Bandwagon
• Bandwagon creates the impression that
everybody is doing it and so should you.
• If you suggest that someone’s claim is
correct simply because it’s what most
everyone is coming to believe, then you’re
committing the bandwagon fallacy.