I searched for, and failed to find the essay "Paulo Coelho on the Inspiration Behind Veronika Decides to Die" so I decided to type it up by hand because it was worth sharing. Please note the statistics about Canada are no longer up to date, but are still relevant.

About the author: http://en.wikipedia.org/wiki/Paulo_Coelho

About the novel (no real major spoilers, but it's not a spoiler kind of book): http://en.wikipedia.org/wiki/Veronika_Decides_to_Die

From Paulo Coelho on the Inspiration Behind Veronika Decides to Die:

According to Statistics Canada, forty percent of people between fifiten and thirty-four, thirty-three percent of people between thirty-five and fifty-four, and twenty percent of people between fifty-five and sixty-four have already had some kind of mental illness. It is thought that one in every five indivduals suffers from some form of psychiatric disorder.

I thought: Canada has never had a military dictatorship and it's considered to have the best quality of life in the world. Why then are there so many mad people there? Why aren't they in mental hospitals?

That question led me to another: What exactly is madness?

I found the answers to both those questions. First, people aren't placed in mental institutions if they continue to be socially productive. If you are capable of getting to work at 9:00 AM and staying until 5:00 PM, then society does not consider you incapacitated. It doesn't matter if you sit in a catatonic state in front of the television from 5:01 PM until 8:59 AM. You may indulge in the most perverted sexual fantasies on the Internet, stare at the wall blaming the world for everything and feeling generally put upon, feel afraid to go out into the street, be obsessed with cleanliness or lack of cleanliness, or suffer from bouts of depression and compulsive crying. As long as you can turn up for work and do your bit for society and you don't represent a threat. You're only a threat when the cup finally overflows and you go out into the street with machine gun in your hand, like a character in a child's cartoon, and kill fifteen children in order to alert the world to the pernicious effects of Tom and Jerry. Until you do that you are deemed normal.

And madness? Madness is the inability to communicate.

Between normality and madness, which are basically the same thing, there exists an intermediary stage: it is called "being different." And people were becoming more and more afraid of "being different." In Japan, after giving much thought to the statistical information I had just read, I decided to write a book based on my own experiences. I wrote Veronika Decides to Die in the third person and using my feminine ego because I knew that the important subject to be addressed was not what I personally experienced in mental institutions, but rather the risks we run by being different and, conversely, our horror of being the same.