A small study published in the journal Behaviour Research and Therapy found that Socratic questioning can help people with depression to improve their mood by challenging self-destructive thoughts. 

Socratic questioning gets its name from the Greek philosopher Socrates, who used series of questions to help his students exercise critical thinking to come to a conclusion on their own, rather than being handed the answer. 

Within the context of CBT, the method consists of the therapist asking a series of guided questions that help a patient to reconsider harmful perceptions of themselves and the world.

"Using Socratic questioning ... therapists teach clients how to ask themselves questions in order to develop new perspectives and solutions on their own, as opposed to therapists simply providing these solutions directly to the client," Justin Brain, a doctoral student at Ohio State University and the study's lead author, told The Huffington Post. "The therapist models the behavior and skills that we want the clients to learn and develop more fully."

Socratic questioning doesn't have to be done by a therapist -- anyone looking for relief from negative thoughts can try the technique on themselves. 

A therapist might, for example, use the following line of questioning with a depressed patient who is struggling with feelings of failure in the wake of a divorce: Is everyone who experiences divorce a failure? Can you think of anyone for whom that is not true? What evidence is there that you have succeeded, and thus have not been a "total failure"?

Braun offered another example of a Socratic dialogue between therapist and client: 

Client: I'm a failure.

Therapist: What makes you say that?

Client: Well, I keep missing deadlines for my reports at work.

Therapist: ?And how does that translate to you being a total failure?

Client:  I can't even do my job right. I must be a failure.

Therapist: Are these reports your only responsibility at your job?

Client: Well, no. They are just the summary of my work.

Therapist: How do you perform with your other responsibilities at work?

Client: Actually, I do pretty well with my other responsibilities. It is really the report writing that gets me.

Therapist: OK, and what percent of your job would you say is report writing?

Client: Hmm, I would say probably 5 percent or so.

Therapist: So, your reasoning for being a failure is that you can't do your job right, but when we dig a little deeper it looks like, in fact, you do pretty well with about 95 percent of your responsibilities at work. How does this new information fit in with the idea that you can't even do your job right and are thus a failure?

Client: Well, I guess I was not thinking about it this way. I guess if I am doing 95 percent of my job right I can't be failing.

Therapist: So, how might you rephrase your initial negative beliefs to highlight this new information?

Client: When I look at the bigger picture, I guess I am actually pretty good at my job, but struggle with a very small portion.

To examine the effects of Socratic questioning, the researchers studied 55 people with depression as they underwent a 16-week course of cognitive therapy. At the beginning and end of each session, the participants answered questions about their mood and mental state.  

Researchers found that after sessions in which the therapist used more Socratic questioning, the patients reported feeling greater relief from depressive symptoms. 

CBT operates on the basic principle that a person's moods and sense of self are intimately linked with their thoughts, and that recognizing dysfunctional thought patterns and replacing them with healthier ones can lead to improvements in mood.

Techniques like Socratic questioning are designed for patients to be able to perform them on themselves. Ohio State University psychologist Dr. Daniel Strunk told Nature that CBT trains patients in the skills they need to "become their own therapists." 

This training in self-inquiry may be one of the reasons why CBT is so successful. While it's not a blanket solution, research has shown it to be one of the most effective methods for treating depression, with up to 66 percent of patients no longer meeting diagnostic criteria for depression after a single course of treatment. 

"Patients are learning this process of asking themselves questions and being skeptical of their own negative thoughts," Braun said in a written statement.