Hello Robinalex and welcome to PC,

I like your question! It's a good one! But kind of hard to answer in 25 words or less. LOL

I DO know about depression. My diagnosis is Bipolar II and have experienced one or more forms of depression since I was a child some 57 years ago. I've studied it for a long time, too. In Bipolar II, the primary manifestation is depression, as opposed to Bipolar I where it's mania.

The way a person thinks doesn't "cause" depression. It can be caused by many things. Does it "lead" to depression, or promote depression, perhaps your state of mind may predispose you to supporting the development of depression. Most mental health professionals will tell you that major depression is caused either by a major stressful event or by a genetic disorder. If it occurrs in response to a stressful event (death of a loved one, divorce, bankruptcy, major loss, etc.) it can be treated and recovery can occurr. If it occurrs because of a genetic predisposition, sometimes how you think has no effect whatsoever upon whether or not you develop major depression. You either will or you won't, because if the gene is there, it's there and if something triggers it, that's the end of the story.

This is my two cents worth. I am not a professional. I am a professional patient.