I just finished Original Sin, by Alan Jacobs (HarperOne, 2008) who is best known for his biography of C.S. Lewis (which I have been meaning to read). Amazing book. The key is the title description: "A Cultural History." Though the book is a chronological look at the history of the theology, most of the sources aren't known Christian specialists. I would describe the book more as a philosophical history with a strong emphasis on the Christian aspects. The book goes into fascinating viewpoints, always careful to show both sides. Though Alan Jacobs's opinion is obvious, he does not force his conclusions upon the reader, but allows them to draw their own based upon the mountains of research he has done.
The book is essentially a look at the natural instinct of humanity and the different figures who have advocated for both the saints and sinners.The book starts with Augustinian beliefs and the ancient church, but quickly moves on to examining Milton's Paradise Lost and the fall itself, frequently referencing Genesis, but paying attention to the language that notable poets and authors have used. Over the whole of it, Jacobs focuses on genetics (Is goodness/badness inherited? What are the implications of the conclusion?), slavery (Are we all equally bad? If those of different races are equal in morality, how can we justify slavery?), education (Should children be raised with strict discipline, or left to nature's whims?), and economics (If Marx believes in the good of society collectively, and Smith believes in the individual and the invisible hand, aren't both essentially saying humanity will make the best choice? Is there an alternative?). I've found the book's conclusions to be fascinating, and Jacobs has compiled it all with witty humor and tasteful jabs at historical figures.
The most important thing I am taking away from it is that history has proved through countless acts of violence and deceit that humanity, left to its own, is sinful. Jacobs points out that this drives many people away from it, or those who accept it feel there must be more to it. Many people who have advocated against the doctrine of original sin did so to deter complacency among the congregation; they were worried that people would use their "nature" as an excuse for their behavior. However, the acceptance of that doctrine should only encourage those who are struggling that they are not the only one. Furthermore, it only emphasizes the grace of God.
Again, I highly recommend Original Sin:A Cultural History. It's easy enough to understand if you have a mediocre grasp of world history and significant events/literary works (basically everyone I know...). I found it at the Calgary Library, so I'd recommend checking a local library. If you do take my advice, let me know what you think! ;)