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PREFACE: WHY IS THIS SO CONFUSING?
Students and other readers sometimes comment that the problems presented
in the analytical reasoning section of the LSAT (A.K.A. the logic games) seem
overly confusing and unnecessarily difficult. Sometimes people ask, “Why didn’t
you just say . . . ” or “Why don't you say everything the same way?”
The answer to those questions and the source of the apparent confusion has to
do with understanding the structure of the LSAT Logic Games, and, by extension, an
essential element of the LSAT test itself. Remember, the goal of each logic game is
to improve the ability to work with the LSAT analytical reasoning section efficiently and effectively.
Consider this example from an actual LSAT test:
Nine different treatments are available for a certain illness:
three antibioticsF, G, and Hthree dietary regimensM, N, and Oand three physical therapiesU, V, and W. For each case of the illness, a doctor will prescribe exactly five of
the treatments, in accordance with the following conditions:
If two of the antibiotics are prescribed, the remaining
antibiotic cannot be prescribed.
There must be exactly one dietary regimen prescribed.
If O is not prescribed, F cannot be prescribed.
If W is prescribed, F cannot be prescribed.
G cannot be prescribed if both N and U are prescribed.
V cannot be prescribed unless both H and M are
This information sets up a situation, then asks six questions about it. Take a
look at the list of conditions. The first two have to do with the number of treatments
that might be prescribed from two of the categories. The second of these
conditions is quite clear: There is exactly one dietary regimen prescribed.
However, the first condition does not seem nearly so clear. It defines a
relationship among the antibiotics: “If two of the antibiotics are prescribed, the
remaining antibiotic cannot be prescribed.” Spend a little time analyzing that
statement and you will see that it is much simpler than it appears, and means:
“the doctor does not prescribe all three antibiotics.” The statement leaves the possibility
that the doctor prescribes one or two of the antibiotics, but not all three.
Understanding the situation requires the ability to make that analysis.
The remaining four conditions establish relationships among some of the
treatments that the doctor’s prescribing follows. But it takes a bit of time to
sort out exactly what these conditions are, since they are expressed differently
from one another. The second condition is the most clear and straightforward
of the four. It says that, If W is included, then F is not.
That seems pretty plain, so let’s try to make the other three conditions clear
in the same way. The first of the three conditions includes two negatives, so you
can clarify it by removing those negatives, revealing that it means exactly this:
If F is included then O is also included. Now follow through this form with
another condition, which involves multiple items and seems to reverse the order
of the statement. It turns out to be: If both N and U are included, then G is
also included. The relationship in the last condition is in a different format and
uses the word “unless.” But you can make it clearer when you put it in the same
form as the other three conditions, which makes it into two statements: “If V is
included, then H is included,” and “If V is included, then M is included.” This
analysis takes these seemingly confusing conditions and makes a list that is easier
If F is prescribed then O is also prescribed.
If W is prescribed, then F is not prescribed.
If both N and U are prescribed, then G is not prescribed.
If V is prescribed, then H is prescribed.
If V is prescribed, then M is prescribed.
Applying all of these conditions at the same time will be a challenge, but it
helps to understand exactly what they mean.
In this example, we stated all the conditions in the form originally used by
the second condition (a positive), but they could also be stated in the form of the
first condition and mean exactly the same thing. Stated that way, they become
If O is not prescribed then F is not prescribed.
If F is prescribed then W is not prescribed.
If G is prescribed then N is not prescribed or U is not prescribed.
If H is not prescribed then V is not prescribed.
If M is not prescribed then V is not prescribed.
This way of stating the conditions seems more cumbersome, but it means
exactly the same thing. We could also state it several other ways. Suppose we put
all the conditions in the form using “unless.” Then they become:
O is prescribed unless F is not prescribed.
W is not prescribed unless F is not prescribed.
Unless G is not prescribed it cannot be that both N and U are prescribed.
V cannot be prescribed unless both H and M are prescribed.
To most people, this would be the most confusing of the three formats, but
the statements mean exactly the same thing as in the other two examples.
In this LSAT problem, a mix of formats is used, which creates opportunity
for error in interpretation. Those errors have to be avoided to be able to understand
the situation and to demonstrate that the consequences of the conditions
include things like “O could be prescribed without F” or “N and G could both
be prescribed,” deductions that are likely to crop up in the questions.
Now if we were writing, say, a technical manual about how to hook up a
printer to your computer or, perhaps, an academic paper about the possibilities
for the control of Congress in the coming election, two things would guide
our choice of how to make the statements: we would want to make it easiest for
the reader to understand what we mean, and we would want to be consistent
in the form we use from statement to statement. That is because in those
settings the goals would be clarity and accuracy. But in the LSAT students are
not being tested about their own clarity, but about their ability to understand
the meaning of complex statements and to apply that meaning in various circumstances.
For that reason the LSAT does not necessarily seek the clearest way
of making a statement, and it certainly does not follow the same format for every
similar condition. The goal is to understand the test-taker’s ability to interpret
various ways of making the statements correctly, and so that is what is tested. To
be sure, in any analytical reasoning section the statements are all exact in that
there is no ambiguity and that each says what it means to say.
In this particular analytical reasoning example, the conditions are stated
in various forms that might leave the test-taker, and especially a more casual
reader, asking: “Why don't you just say what you mean?” The answer is: “Because
I want to discover your level of ability to understand the complexities of language and
And that is exactly what this book is designed to help you practice: correctly
interpreting complex statements to understand what they mean and what they
don’t mean, so you can combine them with other such statements to discover their
implications, and then answer questions.
In an analytical reasoning situation, one misinterpretation of one condition
is likely to lead to several incorrect answers. In most cases, there are several conditions
in any situation, and they are often stated in a variety of ways.
In the example, the conditions may seem confusing. But that is not because
they are confused about what they mean, and not because their meaning is
ambiguous. They seem confusing because of the variety of ways to say the same
exact thing. As you study for the LSAT you will benefit from learning the
meaning of these various linguistic forms.
Someone who wants to excel on analytical reasoning problems must master
these formats in order to avoid making mistakes and to succeed in working the
problems efficiently and effectively.