An ad hominem argument rejects or dismisses another person's
statement by attacking the person rather than the statement
There are many different forms of this fallacy, but all of them
involve some attempt to avoid dealing with a statement logically,
and in each case the method is to attempt to discredit the
speaker by citing some negative trait. An ad hominem argument
has the form:
X says p. X has some negative trait. Therefore, p is false.
This is a fallacy because the truth or falsity of the statement
itself, or the strength of an argument for it, has nothing to do
with the character, motives, or any other trait of the person who
makes the statement or argument.
In its crudest form, the ad hominem fallacy involves nothing more
than insults--calling one's opponent an idiot, slob, lowlife,
airhead, fascist, pinko, nerd, fairy, bleeding heart, wimp,
Neanderthal, and so on--using the rich vocabulary of abuse our
But the fallacy can also take more sophisticated forms. Let's
look at two of them.