Hi,

Well, it's an interesting and very useful question because one of the debates is whether depression is a disorder of mood or a disorder of thinking. The medical approach tends to be towards the treatment of depression as a disorder of mood, meaning there is an assumed imbalance in your biology that needs correcting (with medication).

Many psychologists believe that depression can result from a way a person thinks about their situation (often negative), and the beliefs and consequences of their actions. Cognitive Behavioral Therapy, CBT, has a very good track record of success. Some therapists find that a combination of antidepressants and CBT is effective.

So, although your question asks about the difference between clinical depression and attitude, the question suggests a dichotomy which may not actually exist.