There’s an interesting story in the Deseret News entitled A simple explanation works best for the Restoration. I’ve included the first bit here, but read it in its entirety and let me know what you think.
We left off last week with the notion that the Book of Mormon was plagiarized from a manuscript written by Solomon Spalding, who had died in 1816. Sidney Rigdon, so the story goes, stole the work from Spalding’s family and, for whatever reason, used it to set the young farmer Joseph Smith up as a prophet.
Though lacking any real historical support, this was the dominant non-Mormon theory of the origin of the Book of Mormon for more than a century. In recent decades, though, it’s fallen on hard times.
It didn’t help, probably, that, when Spalding’s lost manuscript was found, it was also found to bear no significant resemblance to the Book of Mormon.
Still, much like doomsday cultists when the date of their predicted apocalypse passes uneventfully, the Spalding faithful soon regained their balance: There was, they declared, a previously unknown and still unseen second manuscript that would, no doubt, prove to be the source of the Book of Mormon when and if it were ever actually discovered.
Few dispassionate observers doubt that, if such a second manuscript ever actually turned up and failed to fit their requirements, they would shortly be proclaiming the existence of a third hypothetical manuscript.
For this and many other reasons, few serious scholars, if any—whether believing Latter-day Saints or not—pay the Spalding theory much attention any more. Even the late Fawn Brodie, no friend of Joseph Smith or Mormonism, denied Solomon Spalding any role in the production of the Mormon “keystone” scripture.