16 SMART THINKING: SKILLS FOR CRITICAL UNDERSTANDING & WRITING
words, and not that Hussein was such a person. The claim 'Saddam Hussein was
an evil dictator' here serves as the predicate to the subject 'George W. Bush',
connected with the word 'said'. Thus, if we were to assess the truth of the claim, it
would do no good to see whether or not Hussein was a dictator or evil (even though
we probably could find much evidence to support that point), because the claim is
about what Bush said. These claims, which are essentially concerned with what
others have already claimed, are vital: we often wish to reason about another's point
of view and thus must understand how to make claims about that person and their
words.
A second and even more important use for claims within claims can be found
in claims that use propositional logic, that is, claims taking the 'if..., then...' form
so common in contemporary philosophy and computer programming. Such a
claim is, for example, 'If I am unwell, then I should go to the doctor'. Now it might
look as though there are two claims here: and, indeed, there are. However, by
placing two claims in an if/then relationship, each claim becomes a subsidiary part
of a single, much more powerful claim. What is actually being asserted in the
if/then claim is not the substance of one or the other claim but, rather, the
relationship between them. Hence 'If I am unwell, then I should go to the doctor'
asserts that it is reasonable to do something (go to the doctor) when a particular
state of affairs (feeling unwell) occurs. We will see the importance of these special
'if/then' claims in chapter 3.
Exercise 2.4
Identify the claims within a claim here, remembering that an entire claim can
serve as either predicate or subject.
a. I have been told by my doctor that drinking milk makes some people feel
sick.
b. If I drink milk, then I feel sick.
c. If a person comes to a doctor and says 'If I drink milk, then I feel sick',
then the doctor will diagnose that person as lactose-intolerant.
Scope and certainty
A statement that makes a claim about the world allows us to judge the truth or
falsity of that statement. In making this judgment, we need to consider the scope of
the claim. For example, each of these claims has a different scope:
- All Australians think global terrorism threatens this country.
- Some Australians think global terrorism threatens this country.
- A few Australians think global terrorism threatens this country.
The claims are very similar, except in their reporting of the number of
Australians who believe global terrorism threatens their country. The scope, in each