Valid
vs. Invalid Uses of the Lines of Argument
Arguments
are valid and ethical when both the evidence and logic are well-established and
have been repeatedly tested and independently verified, and the outcome of the
argument will have a beneficial result for those involved. But it is rare that
we will have the opportunity to test all the available evidence for the
majority of arguments we will be faced with, and most often we are forced to
base our own arguments and opinions on the evidence and logic of others.
Ethos:
Credibility and Authority
Credibility:
trustworthiness
Authority: knowledgeable
A
"credible authority" is someone whose information you can trust.
Technically speaking, we don't actually trust the person but the
person's ability to supply valid information.
Valid Use of Ethos: Einstein was a credible authority on the theory of relativity because his argument was based on strong evidence and logic. People were willing to study and test his theory because of his credibility and authority. No one, however, "trusted" his theory was correct simply because "Einstein said so."
Invalid
Arguments Abuse Ethos in Two Ways:
1)
Claims to Authority: People in power are "right".
Einstein's theory of relativity must be right because he was right
about a lot of other things. Bush's plan for providing federal funding for
"faith-based organizations" must be good because Bush is the president
and he is a Christian. Bush's plan
obviously doesn't violate the separation of church and state because if it did
Bush, who is president, wouldn't have offered it.
2)
Ad Hominem: People you don't like are "wrong" or
confusing the person making the argument with the argument itself.
Einstein's theory of relativity must be wrong because Einstein built the
bomb that killed so many innocent people. Bush's
plan for federal funding of "faith-based organizations" must be bad
because Bush used drugs; or, the plan must be bad because Bush received so much
campaign aid from Christian organizations that will receive said funding.
(Both attack Bush "the man" and his motivation instead of the
arguments itself).
Appeals
to Values: It is logical and
valid to show the similarities between the values of related topics and to
persuade an audience toward a new value by showing its relationship to existing
values. One must be careful,
however, of "values" that are so broadly defined that they are
meaningless (Glittering Generality).
Valid
Appea
Invalid Appeal to Values: It's un-American to use drugs, so anyone who argues for the legalization of marijuana is un-American.
"We need honest, reasoned debate; not fear-mongering. To those who pit
Americans against immigrants, and citizens against non-citizens; to those who
scare peace-loving people with phantoms of lost liberty; my message is this:
Your tactics only aid terrorists - for they erode our national unity and
diminish our resolve. They give ammunition to America's enemies, and pause to
America's friends. They encourage people of good will to remain silent in the
face of evil." -- Testimony of Attorney General John Ashcroft
Senate Committee on the Judiciary
December 6, 2001