One of the major impediments to effective communication is faulty or fallacious reasoning. A fallacy is any fault in logic or reasoning, or any misconception arrived at by means of faulty reasoning. Fallacies can be made either intentionally or unintentionally. When made intentionally, they are generally obscured by a rhetorical ploy in an attempt to exploit, confuse or manipulate an interlocutor or listener. When used unintentionally, however, they can oftentimes lead to misunderstandings between parties involved in otherwise candid communication.
Effective communication requires that a number of simple conditions be met in order to make sure that there are no misunderstandings between parties in an exchange. First, speakers should try to express themselves accurately, clearly and correctly. They should refrain from rhetorical flourishes or speaking patterns which could confuse a listener, and they should relay information directly. Second, interlocutors should listen carefully to one another. They should ask for clarification whenever necessary. Finally, interlocutors should not jump to conclusions or make faulty assumptions about what the other party intends to say, already knows or can figure out on their own. Points should be made as explicitly as possible.
Formal fallacies are structural flaws in deductive reasoning which render an argument invalid. There are many kinds of formal fallacies, but the most common ones are generally made without people being aware that they have made them at all. This, in turn, can impede effective communication. Strictly speaking, a formal fallacy is different from a factual fault, because it results from a purely structural error in reasoning about a set of propositions; if the propositions are factually false, but the conclusion itself is follows logically, an argument is still technically sound, even if it is factually incorrect.
While formal fallacies occur because of a flaw in the logical structure of an argument, informal fallacies occur because of flaws in the content of the argument. There are many kinds of informal fallacies, and any given argument may commit more than one at the same time, but generally they can be broken into three kinds. The first are fallacies of ambiguity. These occur when the meaning of a premise or conclusion is unclear.
The most common of these is equivocation, which occurs when a phrase is interpreted or defined in the argument in two or more different ways. The second are fallacies of presumption. These happen when a premise or conclusion is already assumed true before the fact. This can oftentimes lead to tautological statements, such as “the rules are the rules.” Finally, there are fallacies of relevance. These occur when an irrelevant premise is introduced into an argument in order to draw a faulty conclusion. These occur often in political discourse, usually when an insult is used in place of a reasonable argument.
Verbal fallacies are also fallacies of ambiguity, but they occur most frequently in spoken discourse. For example, ambiguity can arise in spoken discourse because the emphasis or stress of a sentence is unclear. If one says “SHE seems happy,” this has a different meaning from “she SEEMS happy.” If the stress is not clear, the meaning can be confusing. Likewise, verbal fallacies can occur when a statement is taken out of context, because the tone of and situation of the utterance is not clear.
Sometimes effective communication can fail because interlocutors assume they understand and abide by the same rules of interaction. This is not always the case, and to falsely assume that communication signals function between cultures can oftentimes cause otherwise clear communication to break down. For example, if Ting comes from a culture where it is disrespectful to stand close to others while speaking to them, while Pedro comes from a culture where it is rude not to stand close to an interlocutor, there is the chance that an awkward and confusing communication situation will arise, because each may think the other is being rude for simply following their own cultural norms.