On October 23rd, 2014, we updated our
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Begging the Question
A logic lapse committed when, instead of offering
proof for its conclusion, an argument simply
reasserts the conclusion in another form.
"Death for traitors is justified; because it is right
to put to death those who betray our country."
"Why did he lose the election? He didn’t get
"When many people are out of work,
unemployment results." (Calvin Coolidge.)
Some questions contain implicit assumptions,
which may not be true. It is important to question
"Have you stopped beating your wife?"
"Why is a ton of lead heavier than a ton of
"Will you be paying by a check or a credit card?"
"Would you rather watch your baby sister or mow
The attempt to prove a conclusion that is not
the one at issue.
"The United States had justice on its side in
waging this war. To question this would give
comfort to our enemies and would therefore be
"Vegetarianism is an injurious and unhealthy
practice. For if all people were vegetarians, the
economy would be seriously affected and many
people would be thrown out of work."
Fallacy of Absent Control (False Cause)
People commonly declare their washing their car
enhances the chances of there coming up a
rainstorm. "Every time I wash my car, it rains", they
say. Well, maybe so, but the question is, how likely
is it to rain if they don't wash their car?
"Twenty-five years after graduation, alumni of
Harvard College have an average income five
times that of men of the same age who have no
college education. If a person wants to be
wealthy, he or she should enrol at Harvard."
Ad Hominem a.k.a.: Attacking the Person
A persuasion strategy in which a person attempts to
defend her own position by pointing out the
undesirable associations, personal characteristics, or
motives of those who do not accept it.
The impact of the suggestion that "only bad people disagree
with me" is often supplemented with an "all good people
agree with me", introducing an appeal to diffuse authority.
The big (and overlooked) question is: what has their
badness or your goodness got to do with the truth of your
position? The big (and overlooked) answer typically is
"Smoking is unhealthy. You should quit." "Hey! Look who’s
talking! You smoke!"
Appeal to (Diffuse) Authority
Definition: Defending a claim by citing, as a premise, the fact
someone says or thinks as they do, where this person’s expertise (if
any) is not relevant to the issue at hand, even though he may be
someone who is famous or admired.
Comment: It's not necessarily fallacious, or irrational, to appeal to
the judgment of authorities in support of a given statement. It is
seriously irrational, however, to base your acceptance of a
statement on the word of someone who doesn't know what
they're talking about.
"No federal aid should be provided for public schools. My banker,
my dentist, my doctor, my minister, and all my business associates
are opposed to it."
"I join two presidents, twenty-seven senators, and eighty-three
Congressmen in describing Drew Pearson as an unmitigated liar."
Appeal to Force
Definition: A strategy to reduce the critical impulses
of the listener by demonstrating or implying that it
could dangerous to disagree with these statements.
"You must believe with me that this woman is
guilty of the crime of which she is accused, for if
you do not find her guilty of it, she will be
released and you may end up being her next
"Don’t argue with me, young man. Remember
who pays your salary."
Appeal to Ignorance
Definition: Uses an opponent’s inability to disprove a
conclusion as proof of the conclusion’s correctness.
"No responsible scientist has proved that the
strontium 90 in nuclear fallout causes leukaemia.
Therefore we can disregard the alarmists and continue
testing nuclear weapons with a clear conscience."
"If there were any real evidence for these so-called
flying saucers, it would be reported in our reputable
scientific journals. No such report has been made;
therefore there is no real evidence for them
Appeal to Pity
Definition: Seeking to support a statement by stating or suggesting
that some person or creature the consumer cares about would be
hurt or harmed by not accepting the truth of the proposition.
"Streaks of pain etching his youthful face, the boy drags his withered
legs along the sidewalk, two crutches biting into the pavement one
short step ahead. The minutes seem like hours, but the thinly built boy
finally makes it to his destination, hangs up his coat and prepares for
his day’s activities. When a handicapped boy pains himself by walking
gruelling distances on hard wooden crutches, it proves that the
handicapped will go out of their way to improve their lives. Now we ask
you to do a little out of your way to help the handicapped."
"My client is the sole support of his aged parents. If he is sent to
prison, it will break their hearts, and they will be left homeless and
penniless. You surely cannot find it in your hearts to reach any other
verdict than "not guilty."
Fallacy of Composition - NB
Definition: An argument which requires, but does not
defend, the premise that if all the parts of a whole (or
members of a set) have some quality Q, then the whole
(or set) will also have quality Q.
"They've got Amos McFnerk, the world's greatest centre.Two
fantastic (great) forwards, and two awesome (great) guards.
(Therefore) it's got to be a helluva (great) team!"
"I know one union representative and he is a terrible person. I
wouldn’t trust any of them."
"Under the capitalist system, there are many poor people.
Therefore, capitalism should be abandoned."
Definition: The practice of presenting a
statement with style, volume, exclamation
points, or other indicators of its truth,
importance, or certainty, by way of concealing
its lack of substantiation.
Comment: Yelling is the most common confidence
device. In more cultured circles, one simply
attaches confidence phrases to one's statements–
for example, "Obviously," "As anyone can see,", "Of
course," etc., etc.
Definition: An argument characterized by a long
chain of cause-to-effect inferences, leading from an
apparently innocuous first step to a glaringly
undesirable last one-- the upshot being that one
should avoid the first step if at all possible.
You heard this sort of thing from your third grade
teacher, who said she couldn't let you bring your pet
turtle to school because if she did, then to be
consistent she'd have to let every other kid bring his
pet to school, and who knows, somebody might have
False Dichotomy / ‘Black-White Fallacy’
Definition: An argument which requires such a
statement as a premise, but does not defend it.
"This isn't art-- it's vandalism!" Given the context of
spray-painted graffiti on subway cars, we may assume
that the presenter intended the judgment about art (an
obscure subject) to be strengthened by the judgment
about vandalism (plain to almost anyone). If so, there's
a missing premise, namely "Either it's art or it's vandalism, but
not both." This disjunctive statement may be true, but it isn't
automatically true like "Either it's art, or it's not art" would be.
"We can become independent of Arab oil only
by ruining our environment."
"Volvo: the car for people who think."
"Either you drive a Jaguar, or you don’t drive
"Life is like that, take it or leave it."
"Give me liberty or give me death."
Definition: The practice of disguising simple notions in
complicated terminology, in order to conceal the true
significance (or lack thereof) from the ordinary
Comment: A chemist might refer to what's in the shaker on
your table as "sodium chloride", or "NaCl". You may be
baffled by these terms, but in fact they function to increase
clarity and precision. On the other hand, when the CIA takes
somebody out and shoots him, they may speak of it as
"termination with extreme prejudice", but here the phrase
hides the reality rather than revealing it details.