To throw another log on the fire, can we also make it a point to also draw a distinction between situational "mental illness" and clinical or biological mental illness.
Morgan stated: Greed doesn't directly cause mental issues, having a shitty unfulfilled live can. This can happen regardless of how much money you have, a man struggling to feed himself and someone who has all the money in the world but lacks intellectual and emotional fulfillment are both at risk of depression.
I absolutely agree. However in both cases, the person would be experiencing situational depression, brought on by specific life circumstances. This is an entirely different animal than clinical depression, brought on by a chemical imbalance in the brain chemistry. Either of the above cases could include the additional burden of clinical depression - essentially, take a challenging situation and make it doubly so - but are not themselves a good representation of the mental illness identified as depression.
That being said, it is a chemical imbalance, and in many cases, can be managed by both natural means (diet and exercise do make a difference for almost everyone) and medical ones, if the person can find the correct pharmaceutical and dosage, and mange the side effects. It's frequently misdiagnosed, it's often misunderstood, and it's much more serious than most people realize.
And like all mental health issues, a person's financial circumstances at the onset have no bearing whatsoever on the likelihood of the illness. Wealth is not a protective blanket. It might make the illness easier to manage, but it certainly won't protect you from being betrayed by your own brain chemistry.