ANSWERS, DISCUSSION, AND FURTHER ADVICE 169Exercise 6.7
a The scope and certainty involved make it a strong conclusion. However, the
particular burden of proof involved in proving this conclusion would be
affected by the audience and by its existing commitments to, and under-
standing of, the claim. Serving military officers, for whom national service
involves considerable disruption to their preferred volunteer armed forces,
would need more convincing than, say, a conservative group of older veterans
who themselves had undertaken national service.
b Words like 'one option' and 'some' limit the scope considerably and make it
a mild conclusion. Yet the burden of proof involved in proving this claim to
a group of peace activists, for whom military service would never be an appro-
priate option, would still be very high.
c This is tricky because the claim is stated with certainty but is of fairly
limited scope (not advocating service, but an inquiry). Moreover, the word
'possibility' suggests that the inquiry may not conclude that military service
should be introduced. It is strong, but only in the precise context of the
establishment of an inquiry. Note that, from the perspective of someone
who has already made up their mind that national service should be intro-
duced, a commitment to establishing an inquiry will seem like an opposing
conclusion, especially in a context in which it is often assumed that the
purpose of inquiries is simply to postpone indefinitely difficult decisions
such as this.
Chapter 7
Exercise 7.1
Here are five examples, one of each type. In each case, claim 1 is the conclusion,
and the other claims are all dependent premises in one group.
Reasoning from cause
1 Cigarette smoking is the most significant cause of lung cancer.
2 Almost all people with lung cancer have been exposed to cigarette smoke.
3 Few lung cancer sufferers show any evidence that other causes are responsible
for their disease.
Notice how the two premises establish the common element (smoking) and
also assert that no other factor is usually involved.
Reasoning from generalisation
1 Giulio is not likely to live for much longer.
2 Giulio has lung cancer.
3 Very few lung cancer patients survive their disease for more than a year.