GMAT考试-Testprep数学精解（4）

argument. Finding the suppressed premise， or assumption， of an argument can

be difficult. However， on the GMAT you have an advantage——the suppressed pre

mise is listed as one of the five answer-choices. To test whether an answer-

choice is a suppressed premise， ask yourself whether it would make the argum

ent more plausible. If so， then it is very likely a suppressed premise.

Example：

American attitudes tend to be rather insular， but there is much we can learn

from other countries. In Japan， for example， workers set aside some time ea

ch day to exercise， and many corporations provide elaborate exercise facilit

ies for their employees. Few American corporations have such exercise progra

ms. Studies have shown that the Japanese worker is more productive than the

American worker. Thus it must be concluded that the productivity of American

workers will lag behind their Japanese counterparts， until mandatory exerci

se programs are introduced.

The conclusion of the argument is valid if which one of the following is ass

umed？

（A） Even if exercise programs do not increase productivity， they will improv

e the American worker's health.

（B） The productivity of all workers can be increased by exercise.

（C） Exercise is an essential factor in the Japanese worker's superior produc

tivity.

（D） American workers can adapt to the longer Japanese work week.

（E） American corporations don't have the funds to build elaborate exercise f

acilities.

The unstated essence of the argument is that exercise is an integral part of

productivity and that Japanese workers are more productive than American wo

rkers because they exercise more. The answer is （C）。

Counter-Premises

When presenting a position， you obviously don't want to argue against yourse

lf. However， it is often effective to concede certain minor points that weak

en your argument. This shows that you are open-minded and that your ideas ar

e well considered. It also disarms potential arguments against your position

…… For instance， in arguing for a strong， aggressive police department， you m

ay concede that in the past the police have at times acted too aggressively.

Of course， you will then need to state more convincing reasons to support y

our position

Example：

I submit that the strikers should accept the management's offer. Admittedly，

it is less than what was demanded. But it does resolve the main grievance——

inadequate health care. Furthermore， an independent study shows that a wage

increase greater than 5% would leave the company unable to compete against J

apan and Germany， forcing itsintosbankruptcy.

The conclusion， “the strikers should accept the management's offer，” is stat

ed in the first sentence. Then “Admittedly” introduces a concession； namely，

that the offer was less than what was demanded. This weakens the speaker's

case， but it addresses a potential criticism of his position before it can b

e made. The last two sentences of the argument present more compelling reaso

ns to accept the offer and form the gist of the argument.

Following are some of the most common counter-premise indicators：

Counter-Premise Indicators

but despite

admittedly except

even though nonetheless

nevertheless although

however in spite of the fact

As you may have anticipated， the GMAT writers sometimes use counter-premises

to bait wrong answer-choices. Answer-choices that refer to counter-premises

are very tempting because they refer directly to the passage and they are i

n part true. But you must ask yourself “Is this the main point that the auth

or is trying to make？“ It may merely be a minor concession.

Logic II （Diagramming）

Most arguments are based on some variation of an if-then statement. However，

the if-then statement is often embedded in other equivalent structures. Dia

gramming brings out the superstructure and the underlying simplicity of argu

ments.

If-Then

A——>B

By now you should be well aware that if the premise of an if-then statement

is true then the conclusion must be true as well. This is the defining chara

cteristic of a conditional statement； it can be illustrated as follows