VOX DAY: Dialectic is based on the construction of syllogisms, so it’s very
obvious when one is lying. Rhetoric is “the faculty of observing in any
given case the available means of persuasion.”
It’s not even strictly true to say one CAN lie rhetorically, since an
enthymeme is not a true logical syllogism, all that matters is that the
persuasion is achieved by proof or apparent proof.”
It might be easier to think in terms of “logically sound” and “not
logically” sound than true and false. The point is that I can construct a
logical syllogism that proves or a pseudo-logical enthymeme that
apparently proves, but in either case, they point towards the relevant
truth of the matter.
For example, if I say “SJWs occasionally lie” in response to your
false statement, this is good dialectic but poor rhetoric that is likely
to fail to persuade a rhetorical of the actual truth, namely, that you
are lying in the present circumstance. The better rhetorical statement
is “SJWs always lie”, which is not dialectically true, but persuades the
rhetorical to believe the truth, which is that you are lying.
Hence the importance of knowing your audience. When you speak in
rhetoric to a dialectical, it sounds very dishonest even when it is good
rhetoric in line with the truth. But you can’t speak dialectic to a
rhetorical for the obvious reason that they cannot be persuaded by it.
They simply don’t have the capacity.