I respect your view, but coming from and still in the neuroscience field, I don't agree with any of the science you've explained. Chemicals can influence mood, and even action, before it occurs, as the brain can mimic the process if it is seen performed by someone else. You should look into 'Mirror Neurons'. Anyway, I feel that under-estimating mental health issues and saying "Just be positive" is not the answer because the physical and chemical brain is directly involved.

I fully agree with you about ‘just be positive’ is not an answer. And I hope I didn’t seem to suggest that through what I posted previously. 

To clarify, I don’t discount the fact that there are conditions that could justifiably be classified as a disorder, but given the stigma around the word mental, I guess my personal preference would be to term it a ‘brain disorder’ or something similar, since mental implies deliberate and conscious thought (in my mind anyway). So if a physical defect (I see chemicals as physical as well) exists, then it’s a brain disorder and not a mood/mental disorder. But I suspect my use of such terms interchangeably is probably enough to irk any student of neuroscience, so I’ll stop there. 

I appreciate the exchange. I really do. It forces me to rationalise my views, which is always a good thing. 🙂