44 Unit 2 Critical thinking: the basics
distinction between sub-arguments and main
arguments – is very important, as you will see
when we come to evaluating this argument
and asking whether the reasoning does
adequately support its conclusions.Background information; context
You may also have wondered what to do with
the first sentence: ‘In some parts of the world,
cars are still driven on the left.. .’ You possibly
listed it as a reason. This is not exactly wrong;
in one sense it is because there are some
drive-on-the-left countries that there are
accidents. But there is another way to look at
this which also makes good sense. The first
sentence can be understood as the background
information, or context, for the argument. It is
because of the diversity of traffic rules that
there is an argument to be had.
Neither interpretation would make your
analysis wrong; nor would it make any
difference to an assessment of the success or
failure of the argument. In the interpretation
that follows we have chosen to call the first
sentence ‘context’; but if you prefer to call it a
reason, you can amend the analysis yourself.
As stated in the previous chapter, there is often
room for different interpretations. As long as
you can justify your analysis, and it makes
good sense of the text, you are entitled to give
a different slant.A full analysis
Context: In some parts of the world, cars are still
driven on the left.
R1 Driving on the left can cause
accidents involving drivers from
other countries.
R2 Pedestrians are also at risk from
looking the wrong way.C1 (IC) Cities would be safer if in all
countries the rule were the same.
R3 Countries where drivers keep to the
left are in a minority.Activity
Identify the two argument indicators in [1],
and use them to give an analysis of the
argument.Commentary
With the help of the two connectives,
‘therefore’ and ‘since’, you will have had no
difficulty identifying two conclusions:
C1 Cities would be safer if in all countries
the rule were the same.
C2 Countries where drivers keep to the left
should change over to the right.
The first of these, C1, is drawn from two
reasons (or premises):
R1 Driving on the left can cause accidents
involving drivers from other countries.
R2 Pedestrians are also at risk from looking
the wrong way.
The second conclusion then follows from the
first, making a two-stage argument from R1
and R2 to C1; and from C1 to C2.
To put it another way, we have a sub-
argument – (R1 & R2) → C1 – and a main
argument, C1 → C2. This means that C1
functions as both a conclusion (of one
argument) and a premise (of the other). Hence
we call C1 the intermediate conclusion (IC),
and C2 the main conclusion (MC – or just C).
However, you may have noticed that within
the final sentence there is another reason that
directly supports the main conclusion, namely
that countries where drivers keep to the left
are in the minority. As this is a premise we can
call it R3.
What would you say if you were asked
whether R1 and R2 count as reasons for the
main conclusion? Strictly speaking they are
not: they are reasons for the intermediate
conclusion, and support the main conclusion
only indirectly. C1 is a direct reason for the
main conclusion. So is R3. This distinction
between direct and indirect reasons – like the