logic

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logic
il
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Appeal to Authority
Definition To cite an authority to support a
point as used as ethos only works if the person
is qualified to give an expert opinion on the
subject, other experts agree on the issue, and if
the authority was being serious
Barry Schweid of the Associated Press, in his
efforts to criticize President Reagan's
space-based defense against Soviet missiles, came
up with a report from some Stanford University
group that claimed to find little evidence of
cheating by the Soviet Union on arms-control
treaties. Where were they when Secretary of
Defense Caspar Weinberger and George Shultz,
secretary of state, and several members of our
military forces went on TV and described and
enumerated the different times and ways that the
Soviet Union has cheated on the 1972
Anti-Ballistic Missile Treaty? Does Schweid
really believe that the group at Stanford is more
knowledgeable about U.S. arms-control policy than
all our military experts, with Congress thrown in
for good measure? If I thought that was true, I
wouldn't sleep much tonight. And I doubt if he
would either. (Middleton B. Freeman, "Letters
From Readers," The Courier-Journal Louisville,
April 1, 1987.) The author bases his argument on
the authority of the government defense experts
over another group, solely on the government
groups supposed deeper and more tested
knowledge, rather than necessarily relying on
proven facts.
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Appeal to Common Belief
Definition To use popular belief or opinions of
everyday people in order to verify a claim
Bravery is not enough, said Squealer. Loyalty
and obedience are more important. One false step
and our enemies would be upon us. Surely
comrades, you do not want Jones back? Once
again this argument was unanswerable. Certainly
the animals did not want Jones backBoxer, who
had now had time to think things over, voiced the
general feeling by saying If Comrade Napoleon
says it, it must be right. And from then on he
adopted the maxim, Napoleon is always right, in
addition to his private motto of I will work
harder. (Animal Farm by George Orwell) This is
an example of the power of using mass hysteria
to sway popular belief. By introducing ideas that
appeal to everyones safety and security
(loyalty, obedience, no more Jones) and
associating them with other common beliefs like
Napoleon is always right, one establishes a
succession of appeal to common beliefs.
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Common Practice
Definition To justify an action by claiming that
everyone else in a particular group is following
the same type of action
"They do say," Mr. Adams said to Old Man Warner,
who stood next to him, "that over in the north
village they're talking of giving up the
lottery." Old Man Warner snorted. "Pack of crazy
fools," he said. "Listening to the young folks,
nothing's good enough for them. Next thing you
know, they'll be wanting to go back to living in
caves, nobody work any more, live hat way for a
while. Used to be a saying about 'Lottery in
June, corn be heavy soon.' First thing you know,
we'd all be eating stewed chickweed and acorns.
There's always been a lottery," he added
petulantly. "Bad enough to see young Joe Summers
up there joking with everybody." "Some places
have already quit lotteries." Mrs. Adams said.
"Nothing but trouble in that," Old Man Warner
said stoutly. "Pack of young fools. (The
Lottery, Shirley Jackson) Old Man Warner builds
his argument on the premise it has always been
done that way. He asserts that going against the
flow of common practice, the lottery, will bring
nothing but despair to the community.
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Two Wrongs
Definition To accept something solely on the
fact that everyone else is performing actions
just as bad
The following quote is from the memoirs of
Weather Underground terrorist Bill Ayers,
concerning a bombing attack by the Weathermen on
the Pentagon The operation cost just under
500, and no one was killed, or even hurt. In
that same time the Pentagon spent tens of
millions of dollars and dropped tens of thousands
of pounds of explosives on Viet Nam, killing or
wounding thousands of human beings, causing
hundreds of millions of dollars of damage.
Because nothing justified their actions in our
calculus, nothing could contradict the merit of
ours. (Bill Ayers, Fugitive Days, quoted in
"Radical Chic Resurgent," by Timothy Ash.) The
author compares the wrong of killing in Vietnam
to the wrong of bombing the Pentagon, but states
that since the Pentagon executed wrong actions,
it is appropriate to commit a wrong action
against the Pentagon.
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Indirect Consequences
DefinitionTo reject an action on the basis of
negative outcomes
"If today you can take a thing like evolution and
make it a crime to teach it in the public
schools, tomorrow you can make it a crime to
teach it in the private schools, and next year
you can make it a crime to teach it in the
church. At the next session you can ban books and
the newspapers. Ignorance and fanaticism are ever
busy, indeed feeding, always feeding and gloating
for more. Today it's the public school teachers,
tomorrow the private. The next day the preachers
and the lecturers, the magazines, the books, the
newspapers. After awhile, your honor, it is the
setting of man against man, creed against creed,
until the flying banners and beating drums are
marching backwards to the glorious ages of the
sixteenth century when bigots lighted fagots to
burn the man who dared to bring any intelligence,
and enlightenment, and culture to the human
mind. (Clarence Darrow, cited in Stephen Jay
Gould's Hen's Teeth and Horse's Toes, p.
278.) In this passage, the author slides down
the slippery slope of assuming multiple negative
outcomes that are not necessarily related to the
first event. In other words, the author appeals
to a fear of the reader, but it is absurd to be
able to relate this fear to the first event.
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Wishful Thinking
Definition To change an action on the basis of
potentially extremely positive outcomes
It's what we, the American people, used to take
for granted before the growth of big government
began to shadow our days and smother our hopes.
In the 1980s - when we cut taxes, restrained
regulation, and reduced government spending as a
share of the nation's economy -- prosperity made
a comeback. Jobs were created, incomes rose and
poverty fell for seven straight years. Then the
Democrat-controlled Congress forced the tax hikes
of 1990 and jammed through Bill Clinton's tax
bill of 1993. Our formula for growth,
opportunity, and a better family life is simple
Trust the people, cut their taxes, scale back the
size and scope of government, foster job
creation, and get out of the way. We've done it
before, we can do it again. (Building a Better
America, Republican National Committee) Here
the author uses the events of tax cuts and
reduced government spending to account for a
general happiness. It is a slippery slope that
is used to argue for votes on the basis of a
single events hopefully causing a widespread
general feeling or event, in this case reduced
poverty and elevated incomes, when in fact, the
event may not occur or other events may have
added to the general trend.
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Appeal to Fear
Definition To use force by threatening someone
in order to scare them into action
"The streets of our country are in turmoil. The
universities are filled with students rebelling
and rioting. Communists are seeking to destroy
our country. Russia is threatening us with her
might, and the Republic is in danger. Yes
--danger from within and without. We need law and
order! Without it our nation cannot
survive. (Adolf Hitler, A Campaign Speech,
1932) Hitler uses an appeal to fear by
indirectly stating the results of lack of law and
order. He uses the threat of riot and
destruction to sway the audience in favor of his
bid for elected office.
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Appeal to Pity
Definition To use pity in place of logic in
order to persuade someone into action
One of them a gun was bequeathed to me by my
late father and was purchased by him in the
middle 1920's -- insidious weaponry indeed! Yet I
face the possibility that I could wake up one day
and be felon unless I immediately turn in these
weapons. This is something I will not
do. (Steven Weaver, Freedom's Last Stand. Guns
and Ammo, September 1994.) The author uses a
circumstance or example of an heirloom passed by
a deceased parent in order evoke pity for the
author when that effect was forcefully removed.
The author uses that story to sway the reader
into his argument against gun control.
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Appeal to Spite
Definition An attempt to persuade by using the
disposition a person feels about something or
someone
A Modest Proposal for preventing the children of
poor people in Ireland, from being a burden on
their parents or country, and for making them
beneficial to the publick. It is a melancholy
object to those, who walk through this great
town, or travel in the country, when they see the
streets, the roads and cabbin-doors crowded with
beggars of the female sex, followed by three,
four, or six children, all in rags, and
importuning every passenger for an alms. These
mothers instead of being able to work for their
honest livelihood, are forced to employ all their
time in stroling to beg sustenance for their
helpless infants who, as they grow up, either
turn thieves for want of work, or leave their
dear native country, to fight for the Pretender
in Spain, or sell themselves to the Barbadoes.
I think it is agreed by all parties, that this
prodigious number of children in the arms, or on
the backs, or at the heels of their mothers, and
frequently of their fathers, is in the present
deplorable state of the kingdom, a very great
additional grievance and therefore whoever could
find out a fair, cheap and easy method of making
these children sound and useful members of the
common-wealth, would deserve so well of the
publick, as to have his statue set up for a
preserver of the nation. (A Modest Proposal,
Jonathan Swift) Swift appeals to the British
spite of the Irish. Although this work is
satirical, he uses this spite to make his
modest (absurd) argument appealing.
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Appeal to Loyalty
Definition To support or act in coordination
with the groups best interests, regardless of
the outcomes
Two hundred years ago our forefathers roared for
liberty. Today people whimper for security. Like
a sleeping giant, threads of tyranny are being
spun to keep us down. It's Rip Van Winkle
time...AMERICA, WAKE UP! We need a second
American Revolution. WE'VE GOT ONE MORE HILL TO
TAKE...CAPITOL HILL. This time we'll win with
ballots instead of bullets. There are 24 million
American Veterans who took an oath of true faith
and allegiance to defend our Constitution against
ALL ENEMIES FOREIGN AND DOMESTIC. I can't do it
alone, but (READ II KINGS 615-17). TOGETHER, AS
AMER-I-CANS, WE'LL WIN! Bo is a true American
Patriot who is serious about protecting our
nation, restoring states rights, rejecting global
government, and safeguarding personal liberty. A
RETURN TO CONSTITUTIONAL GOVERNMENT IS OUR BEST
SECURITY FOR AMERICA'S FUTURE! (Colonel James
"Bo" Gritz A Nation Betrayed and Called to
Serve) The author attempts to control the
feelings Americans have about their county he
attempts to use American pride to sway public
opinion in favor of his campaign. By asserting
the goals of any patriot alongside the actions he
will take as a politician, he attempts to gain
votes.
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Appeal to Prejudice
Definition The author uses a predisposed
stereotype or particular attitude against a group
in order to add allure to his argument
Finally, Zhu claimed that his ballyhooed plan to
reform the country's troubled state-owned
enterprises had been "basically achieved" with
their structure having been "somewhat optimized."
That's Communist Party-speak for saying a heap of
problems still remain. Zhu warned that much of
the turnaround came from external factors,
ranging from a booming economy to government-led
debt-for-equity swaps and capacity cuts. The
Premier is worried that some managers have taken
the breathing space as an excuse to relax. Others
are busy stripping assets. (Where Zhu Rongji's
Reforms Fall Short, Mark L. Clifford) The
author uses the Communist-Party stereotype to
assume that the actions of Zhus regime are
inadequate, and appeals to the negative
stereotype the audience has of Communism.
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Appeal to Vanity
Definition To pay compliments toward someone in
order to reach an agreement
"You wouldn't shoot a lady, would you?" the
grandmother said and removed a clean handkerchief
from her cuff and began to slap at her eyes with
it. The Misfit pointed the toe of his shoe into
the ground and made a little hole and then
covered it up again. "I would hate to have to,"
he said. "Listen," the grandmother almost
screamed, "I know you're a good man. You don't
look a bit like you have common blood. I know you
must come from nice people!. "Yes, it's a
beautiful day," said the grandmother. "Listen,"
she said, "you shouldn't call yourself The Misfit
because I know you're a good man at heart. I can
just look at you and tell. (Flannery OConnor,
A Good Man is Hard to Find) In order to save
her own life, the woman appeals to the Misfits
view of himself. She attempts to save her life
by paying compliments to him without actually
knowing the truth about his past or personality.
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Argument from Silence
Definition A hasty generalization in which the
generalization is based on a lack of evidence
rather than incomplete or any evidence
It is a remarkable thing that no canonical
writer ever used nature as a proof of God's
existence. All set out to convince us of it. But
David, Solomon, and the rest never said There
is no void therefore there is a God.' They must
have been cleverer than the cleverest of their
successors, every one of whom has used this
argument. The fact is worth pondering
on. (Blaise Pascal, Lettres a un Provincial -
Pensee 6.) The passage refers to existence of
God being based upon the seeming lack of need for
any evidence, for or against, rather than the
weight of the evidence on one side or another.
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Sweeping Generalization
Definition An argument assuming that everyone or
everything falls into a specific classification,
when the terms of the situation make the rule
inapplicable.
Americans who cherish the nation's diversity
have been alarmed in recent years by efforts to
restrict the consideration of race in public
university admissions policies. (Picking the
Best Student Body, May 15, 2002, New York
Times) The author assumes that all Americans who
cherish the diversity of the nations are also
alarmed by efforts to restrict the consideration
of race, when, in fact, the Americans who cherish
diversity may or may not be alarmed.
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Part for the Whole
Definition A fallacy in which an argument for
the validity of a subgroup or subpart of a
particular group, institution or idea is based
upon the validity of the whole, whereas the parts
may not be of similar merit to the whole.
Should we not assume that just as the eye, hand,
the foot, and in general each part of the body
clearly has its own proper function, so man too
has some function over and above the function of
his parts? (Aristotle, Nicomachean Ethics,
Martin Ostwald, translator, Bobbs-Merrill, 1962,
p. 16) Aristotle assumes that since each part of
the body has a function, the body as a whole must
have a function. In reality, the body may differ
from the parts.
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Whole for the Parts
Definition A fallacy in which an argument for
the validity (goodness, description) is made
based on an example of one particular part of the
institution rather than the whole
After taking power in January, Newt Gingrich
promised to implement his "Contract with
America." The "Contract" is a nasty piece of
work. Together, these policy proposals represent
the biggest attack on workers and the poor since
the 1920s. The Republicans want to throw people
off welfare -- whether they have a job or not.
They want to restrict the rights of ordinary
people to sue corporations. Newt wants to cut
taxes for the rich, raise defense spending and
destroy the National Endowment for the Arts.
These proposals show what the Republicans are all
about -- defending the interests of the rich and
the corporations which financed their election.
(Contract On America How do we stop the
Republicans?, International Socialist
Organization in Seattle, Washington.) The author
assumes that Newt Gingrichs promises and
proposals represent the statements and actions
of the Republican party as a whole, when in fact
the goals of the Republican party may differ from
the actions of Newt Gingrich.
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Ad Hominem
Definition A non rational appeal based on the
person, or the personality or connotation of that
person, rather than upon the validity of the
argument.
Al Gore will say anything and do anything for
partisan advantage.Al Gore wants to blow a hole
in the budget and return us to the days of Big
Government.Get the facts on Al Gore's fuzzy math
and selective memory.Al Gore's fictitious fight
for Campaign Finance Reform. A silent
advocate? (Republican National Committee, RNC
Ad Backgrounder Newspapers) The author attacks
Al Gores personality and honesty in order to
gain support for his or her opposing point of
view--in this case, in order to turn voters
against Al Gore, a Democrat.
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Post Hoc
Definition Assuming that a previous event caused
a latter event.
"The only policy that effectively reduces public
shootings is right-to-carry laws. Allowing
citizens to carry concealed handguns reduces
violent crime. In the 31 states that have passed
right-to-carry laws since the mid-1980s, the
number of multiple-victim public shootings and
other violent crimes has dropped dramatically.
Murders fell by 7.65, rapes by 5.2, aggravated
assaults by 7, and robberies by 3. ("The Media
Campaign Against Gun Ownership, The Phyllis
Schlafly Report, Vol. 33, No. 11, June
2000.) The author easily sets himself up for
fallacy with the word only. Using this word,
the author assumes that the reduction in violent
crimes comes only from the creation of
right-to-carry laws. The author does not give
statistics showing that no other cause was
involved in the reduction of violent crimes. The
two events, therefore, are not necessarily
related.
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Straw Man
Definition Oversimplifying or falsifying the
opponents viewpoints in order to add credibility
or acceptance to your own argument
One other thing I probably should tell you,
because if I don't they will probably be saying
this about me, too. We did get something, a gift,
after the election.A man down in Texas heard Pat
on the radio mention the fact that our two
youngsters would like to have a dog, and, believe
it or not, the day before we left on this
campaign we got a message from Union Station in
Baltimore saying they had a package for us. We
went down to get it. You know what it was? It
was a little cocker spaniel dog, in a crate that
he had sent all the way from Texas, black and
white, spotted, and our little girl, Tricia, the
six-year-old, named it Checkers.And, you know,
the kids, like all kids, loved the dog, and I
just want to say this, right now, that regardless
of what they say about it, we are going to keep
it. (President Nixon, Checkers Speech, in
response to campaign finance scandal) Nixon
admits to the accusations against him. He admits
to accepting campaign donations for his personal
use, but continues and qualifies the gift as a
pet dog he thus reduces the effectiveness of the
argument of the opposition, while still admitting
to the accusations from the opposition.
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Burden of Proof
Definition Shifting the job of proving the
argument to the person to whom you are trying to
prove it. Often, asking another to disprove an
assumed truthful fact. X must be true because
you cant disprove it.
When we entertain, therefore, any suspicion that
a philosophical term is employed without any
meaning or idea (as is but too frequent), we need
to enquire, from what impression is that supposed
idea derived? And if it be impossible to assign
any, this will serve to confirm our
suspicion. (Enquiry Concerning Human
Understanding, David Hume) The author
confirms his suspicion on the basis of the lack
of evidence he asks his audience to disprove for
the sake of setting his own premise.
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Circular Reasoning
Definition Assuming what you are trying to prove
in order to prove it
"To cast abortion as a solely private moral
question...is to lose touch with common sense
How human beings treat one another is practically
the definition of a public moral matter. Of
course, there are many private aspects of human
relations, but the question whether one human
being should be allowed fatally to harm another
is not one of them. Abortion is an inescapably
public matter." (Helen M. Alvaré, The Abortion
Controversy, Greenhaven, 1995, p. 23.) In this
example, the author assumes that abortion is a
moral problem, in order to show that abortion is
morally wrong.
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Loaded Question
Definition A question posed so that each answer
will elicit admittance of the questioners
correctness, or his point-of-view. Usually a
loaded question is a yes or no question.
"Why should merely cracking down on terrorism
help to stop it, when that method hasn't worked
in any other country? Why are we so hated in the
Muslim world? What did our government do there to
bring this horror home to all those innocent
Americans? And why don't we learn anything, from
our free press, about the gross ineptitude of our
state agencies? about what's really happening in
Afghanistan? about the pertinence of Central
Asia's huge reserves of oil and natural gas?
about the links between the Bush and the bin
Laden families?" (Mark Crispin Miller, "Brain
Drain") The author assumes the truth of the
situations he questions, without establishing the
circumstances. He assumes we are hated and
our government brought horror home without
establishing either, while an answer to either
question would admit the truth of what the author
is saying.
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False Dilemma
Definition Black and White Thinking. A person
proposes an statement where a choice between two
items is given, assuming that because one is
false the other is true, when in reality both may
be false one part is not necessarily directly
related to the other.
Is the law founded on unchanging and absolute
principles, or is it like shifting sands, blowing
about with the winds of popular opinion? Is it
drawn from theistic or atheistic and humanistic
foundations, from Mt. Sinai or from Harvard and
Yale law schools? (Cal Thomas, "System reveals
nature of the beast," News-Leader, Monday,
October 21, 1991, 4A.) The author presents only
two options in his question. He makes the reader
choose from two different metaphors when, in
fact, there may be more options for description
of law.
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False Compromise
Definition The combination of two equally
respected arguments that are added and reduced
together to provide a still erroneous, or newly
erroneous conclusion.
In 1994, the United States, having been burned
in Somalia, was desperate to stay out of Rwanda.
How to manage that? By pettifogging. By arguing
about semantics the Clinton way. His
Administration, pressed to honor the 1948
Genocide Convention (not to mention human
decency) by intervening, quibbled at a furious
rate about the meaning of the word genocide.
Madeleine Albright temporized as the death toll
in Rwanda climbed into the hundreds of thousands.
the casuistry pressed into service to dodge an
inconvenient genocide (Lance Morrow Time
Magazine October 12, 1998 Vol. 152 (15) In this
example, the two extreme positions are
isolationism and noninvolvement or involvement
and the stopping of genocide. Clinton
Administration was able to use semantics to come
up with a meaningless and harmful compromise.
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False Equity
Definition An argument which seems appealing due
to its equality to both sides
I like the Walrus best, said Alice, because
he was a little sorry for the poor oysters. He
ate more than the Carpenter, though, said
Tweedledee. You see he held his handkerchief in
front, so that the Carpenter couldnt count how
many he took contrariwise. That was mean!
Alice said indignantly. Then I like the
Carpenter best if he didnt eat so many as the
Walrus. But he ate as many as he could get,
said Tweedledum After a pause, Alice began,
Well! They are both very unpleasant characters
---. (Alice in Wonderland byLewis Carroll) In
this passage the characters are reacting to a
poem, just told by Tweedledee, and the characters
are challenged to determine who is of greater or
lesser value. Their opinions change not on the
strength of the data but, rather, on the
consistent presentation of the data being
presented for one side of the other.