Psychiatry, except in rare cases, does nothing of the sort. Most discussion about mental illness (including your post) is an attempt to induce people to apply fallacious reasoning about it - you've developed intuitions about cancer, now go incorrectly apply that intuition to depression/drug addiction/etc.
http://lesswrong.com/lw/2as/diseased_thinking_dissolving_que...
If you wish to argue that a given animal can fly, "penguins fly just like crows fly, they are both birds" is a fallacious argument. Similarly, "do X for mind disease just like you'd do X for lung disease" is a fallacious argument.
Yes -- except there is no such thing as a "mind doctor", at least in a scientific sense. Psychiatrists and psychologists cannot treat depression, and increasing amounts of neuroscientific evidence demonstrate that depression is not a mental illness, it's a physical one.
A recent study of deep brain stimulation (http://www.nytimes.com/2006/04/02/magazine/02depression.html...) is showing very promising preliminary results, results in which a patient's depression lifts instantly when the stimulating signal is applied, and resumes when the signal is removed. Apart from being a promising indication for future research, this study shows that depression is not a mental illness, the domain of psychiatry and psychology, it's a physical illness, the domain of neuroscience.
In science, the word "probably" is best left behind.
> It is hardly the same as something like diabetes.
But that's just the point -- until we know what causes depression, as scientists we should not arbitrarily assume anything. The recent findings point to a physical, biological cause. The fact that psychiatrists and psychologists cannot treat depression points in the same direction. Or didn't you know that? Studies of psychological depression treatments and drugs have yet to reach statistical significance.
