Screenplay structure is so tight and formal it's almost like poetry, an analogy I found very useful.
My novel (http://www.amazon.com/Darwins-Theorem-TJ-Radcliffe-ebook/dp/...) was developed much more organically.
I'm an experimental physicist, and the process for me was more like setting up an experiment, from early ideas to failed prototypes to little side explorations to a final result with (hopefully) all the loose ends tied neatly away where the reader can't see what went into the making.
I found Stephen King's book on writing to be one of the best for understanding the organic process of creating stories. If you haven't read it, I'd strongly recommend it: http://www.amazon.com/Writing-Stephen-King-ebook/dp/B000FC0S...
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