So much of what’s being communicated in the media these days is irrational, it’s become almost impossible for average voters to separate truth from lie. A short tutorial on irrational logic, including emotional appeals, can sensitize all of us to the ‘earmarks’ of irrational thought—normally the lies—and can help keep all sides honest. You should find what follows and the links below helpful; go back to them frequently to get re-sensitized…I do.

Logical Thinking

Source: Air University

Both verbal and visual support, whether used primarily for emotional or logical appeals, should be backed by logical thinking. Here are some problems that commonly affect logical thinking of persons speaking to the public.

Slanted Reasoning

Slanted reasoning occurs when a speaker makes invalid inferences or reaches false conclusions due to faulty reasoning. Several common types of slanted reasoning follow:

1. The hasty generalization happens when a speaker judges a whole class of objects from an insufficient sample. The person who meets two persons from Alabama and dislikes them, and based on a sample of two, concludes that all people from Alabama are unlikable is guilty of making a hasty generalization.

2. The faulty dilemma stems from the fact that although some objects or qualities can be divided into discrete categories, most cannot. Deeds that are not evil are not necessarily good. A cup of coffee may be neither hot nor cold; it may be lukewarm.

3. The faulty analogy happens when a speaker assumes that two things alike in some way or ways are alike in all ways. The human body and an automobile engine are alike in many respects: both must operate within certain temperature limits, both last longer if cared for, both consume fuel. But you would not argue that since adding tetraethyl lead to gasoline makes an automobile engine run better, people should put tetraethyl lead in their coffee.

4. Stacking the evidence occurs when speakers lift out of context only the support that fits their talk while ignoring equally important material that is detrimental to points they are trying to make.

5. Faulty causal reasoning is seen when a speaker reasons that if A is present, B occurs; further if A is absent, B does not occur; therefore, the speaker reasons that A causes B. Of course it could be that B causes A, or perhaps both are caused by a third ingredient, C.

Irrational Appeals

Irrational appeals depend upon blind transfer of feelings from one thing to another without logical thought. Consider the following examples of irrational appeal.

1. Name calling refers to putting people or things in a bad light by calling them uncomplimentary names such as fatso, warmonger, Seward’s Icebox.

2. Glittering generalities are apparent when speakers wrap their ideas in good, golden, glittering words such as peace, culture, equality, and flag.

3. Bandwagon appeal operates on the principle that “everyone else is doing it so you should too.” Some speakers use the bandwagon appeal to promote the feeling that listeners would be presumptuous to judge for themselves something that the group accepts.

4. “Plain folks” strategy is used when speakers attempt to identify with the simple (and presumably desired) things of life. A speaker who says in front of a farm audience, ”I know how you feel, I was born and raised on a farm, and I want to keep the big city politicians’ hands off your property tax money,” is using plain-folks strategy. Identifying with your audience is a sound practice, but identification alone is not rational support.

5. Prestige or transfer is used by those who drop names or use other strategies to appear important. They believe that simply associating themselves with certain personalities will cause listeners to associate desired traits of those personalities with them as the speakers.

Recognizing Propaganda Techniques and Errors of Faulty Logic

Wikipedia For A more Thorough Logic Treatment