One of the most well-known strategies for dealing with depression is the use of the class of medications know as SSRI's. For many people, Prozac, Paxil, Zoloft, and the like have been incredibly helpful in dealing with depression. Given this, why would a philosopher such as myself have something to say about depression? One reason is that there is another resource which may be helpful in dealing with depression, perhaps in concert with SSRI's and other forms of treatment. That resource is sound critical thinking, and this is something that I am familiar with as a philosopher.
My claim is not that unsound or illogical thinking is the cause of depression, or that the depressed person is blameworthy for how she thinks, but rather that the thinking that is characteristic of someone suffering from depression is sometimes illogical thinking. Such thinking can perpetuate depression. In cognitive therapy, an individual can come to recognize these illogical patterns of thought. Then, through a variety of means, she can begin to change those patterns. We all fall into these patterns of thought at times, but for the depressed they are perhaps more severe or exert more power over their lives. But what sorts of patterns of illogical thought are present in depressed thinking?
There are many issues here worth pursuing. How much can correcting these illogical ways of thinking help the depressed person? How can a depressed person begin to correct this thinking, when it occurs in her mind? I will leave it to the experts in psychology to answer these types of questions, but there is at least good philosophical evidence that sound critical thinking belongs in the toolbox of the person who is dealing with depression, as well as the toolbox of those who are seeking to help such an individual.
Much of the above was drawn from an article published by William Irwin and Gregory Bassham, "Depression, Informal Fallacies, and Cognitive Therapy: The Critical Thinking Cure?" Inquiry (2003): 15-21. Another resource which might be helpful that is discussed by Irwin and Bassham is Feeling Good: The New Mood Therapy, by David Burns.