From that very same book, is the reason my son's middle name is Cain. Because there was a long discussion in it about the story of Cain and Abel and choice.
3. “Don’t you see? . . . The American Standard translation orders men to triumph over sin, and you call sin ignorance. The King James translation makes a promise in ‘Thou shalt,’ meaning that men will surely triumph over sin. But the Hebrew word, the word timshel—‘Thou mayest’—that gives a choice. It might be the most important word in the world. That says the way is open.”
Lee says these words during his discussion of the Cain and Abel story with Samuel and Adam in Chapter 24. He has just revealed to the other men the outcome of the research he did on the meaning of timshel, the word that God utters to Cain when exiling him to the lands east of Eden. According to one translation of the Bible, God orders Cain to triumph over sin, while according to another, God promises Cain that he will defeat sin. Lee’s research, however, has revealed that timshel means “thou mayest,” implying that God tells Cain that he has a choice whether or not to overcome sin. Lee sees this idea of free choice over evil a token of optimism that is central to the human condition. He attempts to convince Adam and Cal of the validity of timshel and ultimately succeeds, as Adam gives Cal his blessing and Cal realizes he himself has the power to overcome his family’s legacy of evil.
http://www.sparknotes.com/lit/eastofeden/quotes.html
Now I don't believe in original sin, but I believe that sins against humanity are possible and of a moral nature, since I'm agnostic, I can't say 'sins against God' which is really what sin means. But the word is useful, in the way the word "evil" is useful. I believe people can make evil, sinful choices that cause great harm and not be mentally ill, or genetically deficient. But I also believe people exist who are mentally deficient in some way; and make evil, sinful decisions as opposed to a choice. Whether its from lack of insight or "moral" compass or something missing--like empathy or altruism
Edit; crap I've read that book 10 times, but it's been 20 years. I really need to read it again
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