The United States Constitution prohibits searches by police officers
unless these officers have adequate reason. That is why the police need
a search warrant before they can search any home. If they fail to obtain
one, a case that ends up in court will likely be thrown out. Our right
to privacy, then, can't be violated without due cause.
If the police can't search our homes without good reason, why should
our head advisor spot-check our rooms for signs of wrongdoing?
Sammy Borchardt
A common and powerful form of deduction called
reductio
ad absurdum
(to reduce to absurdity) is used to attack an opponent's
position by showing that its consequences are absurd if carried to their
logical end. To counter the position that the government should impose
no restrictions on the public's right to bear arms, you might point out that,
carried to its logical extreme, such a policy would allow individuals to own
bazookas, cannons, and nuclear bombs. This absurd result makes it clear
that certain restrictions should apply to our right to bear arms. The question
then becomes where we should draw the ownership line.
Often, a deductive argument is built around a categorical syllogism,
a set of three statements that follow a fixed pattern to ensure sound
reasoning. The first statement, called the
major premise,
names a category
of things and says that all or none of them shares a certain characteristic.
The
minor premise
notes that a thing or group of things belongs to that
category. The
conclusion
states that the thing or group shares
the characteristics of the category. Here are two examples:
Major premise:
All persons are mortal.
Minor premise:
Sue Davis is a person.
Conclusion:
Therefore, Sue Davis is mortal.
Major premise:
No dogs have feathers.
Minor premise:
Spot is a dog.
Conclusion:
Therefore, Spot does not have feathers.
Note that in each case both major and minor premises are true
and the conclusion follows logically.
Syllogisms frequently appear in stripped-down form, with one
of the premises or the conclusion omitted. The following example omits
the major premise: "Because Wilma is a civil engineer, she has a strong
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background in mathematics." Obviously the missing major premise
is as follows: "All civil engineers have strong backgrounds in mathematics."
Syllogistic Argument at Work.
A syllogism can occur anywhere
in an essay: in the introduction to set the stage for the evidence, at various
places in the body, even in the conclusion in order to pull the argument
together. Here is an example that uses a syllogism in the introduction:
In 1966, when the Astrodome was completed in Houston, Texas,
the managers concluded that it would be impossible to grow grass indoors.
To solve their problem, they decided to install a ruglike synthetic playing
surface that was fittingly called Astroturf. In the ensuing years, many other
sports facilities have installed synthetic turf. Unfortunately, this development
has been accompanied by a sharp rise in the number and severity


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- Summer '17
- Jennifer Black
- English, Literature