- Overgeneralization: According to Bassham and Irwin, the "person who engages in overgeneralization sees a single event as a sign of a never-ending pattern of defeat." He reasons from the occurrence of one disappointing important event that all future events will also be disappointing. The event might have to do with work, academic or athletic success, or a relationship, but regardless such thinking is an example of the fallacy of hasty generalization. This occurs when we draw a conclusion about something based on evidence of a small subset. For example, I meet 3 students from Eastern Kentucky University who are all from Ohio, and then wrongly conclude that all EKU students are from Ohio. The same pattern of illogical thinking is present in overgeneralization.
- Mental Filter: This occurs when a person obsessively focuses on one negative detail, resulting in a dark vision of reality as a whole. He zeroes in on this negative detail and filters out everything else. He might focus on one character flaw, a part of his physical appearance he doesn't like, or chipped paint on his new car, but whatever the specifics, his mind locks in on this and excludes the many good things that are present. This is an example of the fallacy of suppressed evidence. This fallacy occurs when we overlook or ignore or unjustifiably discount relevant evidence which supports a different conclusion than what we believe.
- Jumping to Conclusions: In this cognitive distortion, an individual negatively interprets certain facts, and then draws an unwarranted negative conclusion based on that interpretation. There are two major types of this distortion. The first, mindreading, occurs when a person concludes that others think negatively about her without sufficient evidence. An example of this is when a husband interprets his wife's behavior as being angry or disappointed based on some tenuous or insufficient evidence. The other type, the fortuneteller error, occurs when an individual concludes that things will not turn out well in the future when the evidence for this is not present or is inappropriate. For example, a student predicts he will not get into graduate school because he "has a bad feeling" about it. Such thinking can often be a form of the fallacy of insufficient evidence, which occurs when we believe a conclusion even though there is not enough evidence to warrant that belief.
In a future post I'll consider three more ways that depressed thinking is also illogical thinking. As I have thought about this issue recently, my belief that critical thinking can help at least some people suffering from depression has been strengthened. My argument is not that critical thinking should replace medication, though I suspect that in some less severe cases of depression this is a possibility. I suspect more strongly that for a person to more fully recover from depression, he will need to address the thought processes that he's become habituated to engaging in so that he can begin to base his beliefs on better evidence and more reliable logic. This can be easier to do when medication is effective, but it must still be done. Understanding the fallacies present in depressed thinking can be helpful to the person dealing with depression, and to those who are caring for such a person.
