Thinking Skills: Critical Thinking and Problem Solving

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2.4 Identifying arguments 33


2.4 Identifying arguments


Before an argument can be reconstructed and/
or evaluated it must first be established that it
is an argument. This can be harder than it
sounds, especially if the argument is a poor
one. In a good argument the conclusion
follows from the reasons. In a bad argument it
does not follow: the reasons do not justify the
conclusion. It is this which makes it a bad
argument. But how bad does an argument
have to be before we decide that it is not an
argument at all? Establishing that some piece
of text is an argument may come down to
deciding whether or not the author meant or
intended one of the claims to be a conclusion,
and the others to be reasons. Judging an
author’s intention, from a text alone, is not a
very exact science!
Matters are made easier if the conclusion or
reasons are marked by indicators such as
‘therefore’, ‘so’, ‘since’ and ‘because’. However,
these connectives have other functions in the
language beside signalling argument. They
occur frequently, for example, in explanations
(see Chapter 4.2). Just finding two sentences
joined by ‘so’ or ‘since’ does not automatically
identify a reasoned argument. Think of the
words of the rock ballad:


But since you’ve been gone
I can breathe for the first time . . .

There is no argument here. ‘Since’ in the song
means ‘ever since’, which is different from the
meaning it has in front of a premise.
Besides, as stated in Chapter 2.3, there are
plenty of examples of natural-language
arguments which contain no connectives. An
argument may just be conveyed by a pair or
sequence of sentences. Obviously not every
sequence of sentences is an argument. All too


often it is left to the reader to interpret how a
text is best understood.
For example, it is not an argument to say:

[1] Photographs from space show the
Earth’s surface as curved. The curvature
does not show when a photograph is
taken from ground level.

How we can establish that [1] is not an
argument is by asking if either of the two
claims supports the other, or states a reason
for accepting the other. Despite what was
said just now about indicators, a partial test
can be applied by inserting ‘therefore’ or ‘so’
between the sentences and asking: Does it
make sense? If it doesn’t make sense, then
there is no argument – although the converse
does not necessarily apply. Here is the test
applied to [1]:

[1a] Photographs from space show the
Earth’s surface as curved. Therefore the
curvature does not show when a
photograph is taken from ground level.
[1b] The curvature does not show when a
photograph is taken from ground level,
so photographs from space show the
Earth’s surface as curved.

Neither of these makes sense. So [1] is not an
argument.
The same test can be applied to the next
example, only as there are more claims there
will be more rearrangements to try out.

[2] Completed tax forms and payments
must be received by 31 July. Late
payment may result in a fine not
exceeding $100. Your payment did not
reach the tax office until 12 August.
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