Under
the term definition, this section and the next include two different,
but related concepts: first, establishing clearly what the argument is about
(the concern of this section) and, second, defining any key terms essential to
a clear understanding of the argument which is going to use them (the concern
of the next section). The main point here is that an argument cannot usefully
proceed until we all know exactly what the issue is..
In
some arguments, the second requirement (defining key terms) may not be
necessary because the central terms are all clear enough already (although, as
we shall see, that is not something one should assume too readily). In all
arguments, however, especially written essays and oral presentations, the first
requirement is absolutely essential.