On Practical Arguments:
We distinguish two kinds of practical arguments. One is aimed at general rules or
policies for action; the other is aimed at particular actions. These arguments have a very
predictable general shape, which is laid out roughly below. (Note, as a side-point here,
that we always write the conclusions of these arguments in statement form (they are often
originally expressed in imperative sentences). Also, the qualification ‘other things being
equal’ is rarely explicit, but almost always required to make the argument’s premises &
conclusion plausible at all.)
1. Policy arguments:
P: Actions of type A (performed in circumstances of type C) typically have certain kinds
of results.
TP: If actions of type A (performed in circumstances of type C) typically have these
results, then, other things being equal we should (shouldn’t) perform such actions (in
such circumstances).
C: We should (shouldn’t) perform actions of type A (in circumstances C).
2. Arguments regarding a particular action:
P: Actions of type A (performed in circumstances of type C) typically have certain kinds
of results.
TP1: If actions of type A (performed in circumstances of type C) typically have these
results, then, other things being equal we (or some particular agent) should (shouldn’t)
perform such actions (in such circumstances).
TP2: Other things are equal (in this case).
TP3: In this case circumstances are of type C.
C: We (or some particular agent) should (shouldn’t) perform an action of type A (in
these circumstances).