By the time I actually got round to reading this, I was too jaded by the realities of life to take the book's idealism and naive wonder at the insane workings of human nature seriously. The author portrays completely one dimensional ideas which really don't work in a three dimensional world... no matter how cutesy.
So, who is this book written for? Despite the writer's claims, I have a hard time deciding. It seems to be too self righteous and full of platitudes to be really enjoyable to an older audience. As for the children, I really don't think they would understand any of the books ideologies. To them, I guess, its just a strange story about a little prince, in love with a flower. Although, I do imagine they find the opinions about adults quite relatable. I'm no fan of adults myself.
There maybe something wrong with me, but I like my children's stories with a little bit of an edge, a little bit of darkness, a little bit like life, a little bit like A little Princess. It holds no qualms about the fact that shit happens, even if you are a wealthy, sweet, seven year old girl with a bright future. Your dad can die leaving you a penniless orphan, forced into child labor on your birthday. And all this BEFORE you even get a slice of your own cake! Oh, the humanity! Yet, at the same time it teaches us the magic of imagination, having a positive attitude and not giving up your dignity. We should give kids enough credit to acknowledge that they know that the world is both terrible and beautiful. And it would be a much better place if everyone realized, like Sara, that having a crappy life does not justify being an ass.
A little Princess would probably make it in the real world, and The Little Prince would probably get kidnapped while accepting candy (or really bad art work) from a stranger.
Although, the following might have made for a more exciting story line...
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(xkcd comic)