Premise Indicators
because for
since is evidence that
if in that
as owing to
suppose inasmuch as
assume may be derived from
Example:
Since the incumbent's views are out of step with public opinion, he probably
will not be reelected.
Here “since” is used to flag the premise that the incumbent's positions are
unpopular.
Suppressed Premises
Most arguments depend on one or more unstated premises. Sometimes this indic
ates a weakness in the argument, an oversight by the writer. More often, how
ever, certain premises are left tacit because they are too numerous, or the
writer assumes that his audience is aware of the assumptions, or he wants th
e audience to fill in the premise themselves and therefore be more likely to
believe the conclusion.
Example:
Conclusion: I knew he did it.
Premise: Only a guilty person would accept immunity from prosecution.
The suppressed premise is that he did, in fact, accept immunity. The speaker
assumes that his audience is aware of this fact or at least is willing to b
elieve it, so to state it would be redundant and ponderous. If the unstated
premise were false (that is, he did not accept immunity), the argument would
not technically be a lie; but it would be very deceptive. The unscrupulous
writer may use this ploy if he thinks that he can get away with it. That is,
his argument has the intended effect and the false premise, though implicit
, is hard to find or is ambiguous. Politicians are not at all above using th
is tactic.