Logical fallacies can be employed several ways. Politicians engage in sophisticated campaigns engaging in verbal banter. Many variations of logical fallacies can be identified during political campaigns, because people are expecting to be verbally seduced in this manner. To recognize the use of fallacies requires critical thinking skills to sort out the facts, followed by making a decision based on those facts. Recognition of a logical fallacy may create an opportunity for change, once the fallacy has been exposed. Conversely, the fallacy may be entrenched and indicative of a belief system that is unable to be overcome or changed. The following examples will illustrate the use of four logical fallacies.
Logical Fallacies in Psychology
Affirming the Consequent
This fallacy can be described as follows: If x exists, then y is true. Therefore y must also be x.
Example: "People who are psychotic act in a bizarre manner. This person acts in a bizarre manner.
Therefore: This person is psychotic."
Another example: "If this client is competent to stand trial, she will certainly know the answers to at least 80% of the questions on this standardized test. She knows the answers to 87% of the test questions. Therefore she is competent to stand trial." (Pope & Vasquez, 1998)
Application of the above fallacy at initial diagnosis of a client could have disastrous consequences. Assuming the consequence when a person is suffering from a drug induced psychotic episode might lead incorrect diagnosis, subsequently unnecessary medication of temporary symptoms. Failure to rule out antecedents in a case like this may possibly be a form of malpractice.
This fallacy takes the form of assuming that a group possesses the characteristics of its individual members.
Example: "Several years ago, a group of 10 psychologists started a psychology training program. Each of those psychologists...