2.2 Judging claims 25
[G] is another complex claim, and one
which is quite tricky to analyse accurately.
First of all it is not claiming either that parts
of the world will soon be underwater, or that
nothing will be done about climate change.
[G] is what we call a conditional claim, or a
hypothetical. We will also be returning to
these later in the book; but for now all you
need to note is that a conditional is a claim
that if one thing is true, then so is another.
For instance, if nothing is done about
climate change, then parts of the world will
be underwater. If nothing is done and the
prediction turns out to a false alarm, then
[G] as a whole is untrue.Strong and weak claims
Before concluding the chapter, there is one
more important distinction that needs to be
made. Some claims are stronger than others.
The importance of this is that a strong claim
is harder to justify than a weak claim. A
‘strong’ claim is one which says a lot, and/or
says it very plainly or forcefully. A ‘weak’
claim in comparison is more moderate: it says
less, and/or qualifies what it says.
Suppose for example that whoever asserted
[G] had said instead:
[H] Whole regions of the world will soon be
under water as a direct result of man-
made climate change.
This is a very strong claim. It doesn’t say ‘may
be.. .’, or ‘are at risk of being.. .’, or anything
else that softens the impact. It says,
categorically, that whole regions will be
flooded. The whole of [H] is stronger still,
because it also claims, just as categorically,
what the direct cause will be. [H] does not pull
any punches. Moreover, it is clearly implying
that climate change is taking place, and that it
is man-made – a claim that some people deny
or question. It would not make sense to add
that this would be the cause if it were not also
claimed to be a reality. All of these factors add
up to make [H] a strong and far-reaching claim.‘and’, ‘because’, ‘if’.
What difference does it make to the way we
judge a claim if it is complex rather than
simple?
For each of the examples [D]–[G] discuss
the conditions that would have to be met to
justify the whole claim.Activity
Commentary
When assessing complex claims we also have
to take note of the connective, and the
relation it expresses between the parts.
In the case of [D] the job is quite
straightforward. The connective is ‘and’. This
means that [D] as a whole is true if Katya did
just run a marathon and that she ran it in
under four hours. So, if either of these claims
is at all questionable, [D] is not fully justified.
In [E] the connective is ‘yet’ which makes
[E] a slightly more complex assertion than [D].
Again the two connected claims both have to
be true: firstly that dinosaurs were reptiles, and
secondly that they had warm blood. But the
use of the connective ‘yet’ also suggests that
there is something surprising or unusual in
this: that the second claim is true despite the
first being true. The implication is that reptiles
are usually, or normally, cold-blooded; and if
this is not the case then the use of ‘yet’ is not
really justified, even if both the claims are true
in themselves.
[F] also has more to it than just the two
claims. [F] is an explanation, or more
precisely a causal explanation, as indicated by
the connective ‘because’. Its author not only
asserts that sea levels are rising and that
global warming is melting the ice, but also
that the first is caused by the second. If we are
not satisfied that all three parts are true, then
we are not justified in asserting [F]. (There is
more about explanation later in the book.)