And actually I have a preferred way to look at it:

I have ALWAYS believed that "the world is what we make of it" through our actions but also by what we choose to believe and to feel. Although we think we are always behaving based on facts I believe in truth we are behaving based on assumptions and interpretation of events. We can choose to be happy, sad, ANGRY, fearful, based on our beliefs surrounding an event or assumptions of other's motives.

When depression hits it affects us by making ALL of those interpretations and assumptions NEGATIVE. This, to me, is what characterizes depression as opposed to sadness. We lose the power to assign beliefs or emotions to things and people and events and instead everything immediately goes to the worst possible interpretation. Our resulting behavior often triggers more events that are even easier to assign negative thoughts too.

It is a downward spiral that our malfunctioning brains initiate and maintain.

"Thinking Non Depressed" isn't a way to take things from artificially negative to artificially positive. "Artificially positive" may be an intermediate step in the process, but the goal is to break the malfunctioning negative cycle and give us back our power of choice as to how to view the world.