All attempts at persuasion are subject to counterpersuasion. Listeners may be persuaded to accept your claims, but once they are exposed to counterclaims they may change their minds. A one-sided message does not mention opposing claims; a two-sided message mentions opposing points of view and sometimes refutes them. Research suggests that two-sided messages generally are more persuasive than one-sided messages, as long as the speaker adequately refutes opposing claims.⁹

If listeners are aware of opposing claims and you ignore them, you risk a loss of credibility. Yet you need not painstakingly acknowledge and refute all opposing claims. Instead, raise and refute the most important counterclaims and evidence that the audience would know about. Ethically, you can ignore counterclaims that don’t significantly weaken your argument.¹⁰ Chapter 26 describes the refutation pattern of organization, useful for organizing counterarguments.

Fallacies in Reasoning

A logical fallacy is either a false or erroneous statement or an invalid or deceptive line of reasoning. Unfortunately, logical fallacies appear frequently in arguments of all types and can easily evade our detection, leaving us with misrepresentations and distortions of the truth. Reasoned argument as well as critical thinking depend on being aware of fallacies, both in order to avoid making them in your own speeches and to be able to identify them in the speeches of others. Many fallacies of reasoning exist; the following are several that occur frequently in communication.

Begging the Question

Begging the question is a fallacy in which an argument is stated in such a way that it cannot help but be true, even though no evidence has been presented. “Intelligent design is the correct explanation for biological change over time because we can see godly evidence in our complex natural world” is an example of an argument that relies on the kind of circular thinking characteristic of the begging-the-question fallacy. “War kills” is another. In neither statement has the speaker offered any evidence for the conclusion.

Bandwagoning

Speakers who rely on bandwagoning pose arguments that use (unsubstantiated) general opinions as their (false) bases. “Nikes are superior to other brands of shoes because everyone wears Nikes” and “Everyone on campus is voting for her so you should, too” are examples of bandwagoning. The critical listener will ask, “Just who is ‘everyone’?”

Either-Or Fallacy

The either-or fallacy (also called “false dichotomy”) poses an argument stated in terms of only two alternatives, even though there may be many additional alternatives. “Either you’re with us or against us” is an example of an argument posed as an either-or fallacy.

Ad Hominem Argument

The ad hominem argument targets a person instead of the issue at hand in an attempt to incite an audience’s dislike for that person. Examples include: “I’m a better candidate than X because, unlike X, I work for a living” and “How can you accept my opponent’s position on education when he has been divorced?”

Red Herring

In the red herring fallacy, the speaker introduces an irrelevant topic into the discussion in order to divert attention from the issue at hand. For example, “The previous speaker suggests that Medicare is in shambles. I disagree and recommend that we study why the young don’t respect their elders.” This argument diverts attention away from the objective state of Medicare to an essentially unrelated topic: the lack of respect for society’s elders among the youth.

Hasty Generalization

When a speaker uses a hasty generalization, the argument uses an isolated instance to make an unwarranted general conclusion, as in the following examples: “As shown by the example of a Labrador retriever biting my sister, this type of dog is dangerous and its breeding should be outlawed” and “My neighbor who works for Kmart is untrustworthy; therefore, Kmart is not a trustworthy company.”

Non Sequitur

Non sequiturs “do not follow”; that is, the argument’s conclusion does not connect to the reasoning. For example, “Because she lives in the richest country in the world” does not mean that “she must be extremely wealthy.” Neither is it accurate to say, “If we can send a man to the moon, we should be able to cure cancer in five years.”

Slippery Slope

When a speaker uses a slippery slope, he or she is making a faulty assumption that one case will lead to a series of events or actions. For example, “Helping refugees in the Sudan today will force us to help refugees across Africa and around the world” or “If we outsource jobs from the United States, then other companies will outsource jobs, and the U.S. economy will collapse again.”

Appeal to Tradition

Speakers who use the appeal to tradition phrase arguments to suggest that the audience should agree with the claim because that is the way it has always been done. “A marriage should be between a man and a woman because that is how it has always been” is an example of an appeal to tradition, as is “The president of the United States must be a man because a woman has never been president.”