A set of arguments commonly advanced by Latter-day Saints seeking to commend and defend their beliefs cites things that Joseph Smith got right about the ancient world where, humanly speaking, he should probably have been wrong, or forgotten ancient doctrines that somehow reappeared in his revelations or teachings. Such arguments then ask, "How could he have known this?"
A common response from critics to this type of argument is to show, or at least claim, that a roughly contemporary book or source from which he could have derived the particular idea under discussion existed somewhere.
The question then becomes whether the suggested source was part of Joseph’s actual “information environment.” Did he really know about it? Could he reasonably have known?
For example, the notorious “Spalding Manuscript theory” of Book of Mormon authorship fails this test (and would scarcely account for the Book of Mormon even if it didn’t).
Another example: More than 20 years ago, two critics suggested that the cosmological ideas in the Book of Abraham derive from a 1728 entry in Benjamin Franklin’s unpublished personal papers and from an obscure 1755 work by the German philosopher Immanuel Kant that was barely noticed in Germany and wasn’t published in English until 1900.
Other claims are more credible — superficially, anyway: Some critics allege that 1 Nephi’s Nahom, a place name that we now know existed in Arabia during Lehi’s time, could have been taken from Dartmouth College’s copy of Carsten Neibuhr’s late-18th-century map of Arabia, which shows it. After all, the Smith family lived in New Hampshire, not far from Dartmouth, between 1811 and late 1813 — when Joseph Smith was nearing 8 years of age! But, as it turns out, Dartmouth first acquired the map in December 1937, somewhat too late for the 1830 Book of Mormon. (The Library of Congress acquired its copy in 1951.)
Usually, the proposed sources aren’t so manifestly implausible. Still, taken together, they pose a different but equally imposing problem: They seem to demand an impossibly large library for Joseph Smith, whom his mother described as having been, of all her young boys, the least inclined to read. Furthermore, we know what was in the tiny Manchester New York Library in Joseph’s day, and that it charged a membership fee that the Smiths couldn’t afford and didn’t pay.
Sometimes, an efficient response to certain criticisms is simply a good laugh. Members of The Church of Jesus Christ of Latter-day Saints have understood this from their earliest beginnings, as demonstrated, for instance, by Parley Pratt’s 1844 “Dialogue between Joseph Smith and the Devil” and the 19th-century satirical journal “Keep-A-Pitchinin,” written by, among many others, such luminaries as Orson Pratt of the Quorum of the Twelve Apostles, and edited by the eldest son of President John Taylor.
My colleague William Hamblin and I have long toyed with writing a humorous article titled “Joseph Smith: The Cambridge Years,” in which we would demonstrate that, while conventional historians imagine that Joseph spent his youth working on small farms in the northeastern United States, he was actually studying at the finest universities of England and the Continent, gathering materials for his proposed Book of Mormon. And the incomparable Jeff Lindsay, whose “Cult Master 2000” software package is also not to be missed, has actually written a brief script titled “A Day in the Life of Joseph Smith, Translator Extraordinaire” that makes the weaknesses in many critics’ proposals hilariously obvious.
Explanations for Joseph Smith and, particularly, for the Book of Mormon, have varied widely over the years. (See " 'In the Hope that Something Would Stick': Changing Explanations for the Book of Mormon" online at maxwellinstitute.byu.edu.)
At first, confident that the forthcoming book would be absurd nonsense, critics assumed that “Joe Smith,” a frontier rube, was the author. When the book proved to be surprisingly rich and complex, though, they were forced to invoke various co-authors (Solomon Spalding, for example, and Sidney Rigdon or Oliver Cowdery). But there’s no evidence whatever for such collusion or conspiracy (see Myth, Memory, and "Manuscript Found" and "Examining a Misapplication of Nearest Shrunken Centroid Classification to Investigate Book of Mormon Authorship" both online at maxwellinstitute.byu.edu), and critics were again obliged to fall back on Joseph Smith as sole author.
However, no explanation that adequately and consistently accounts for the entirety of Joseph’s testimony and revelations has yet been proposed. The hypothetical explanation offered for X seldom also covers Y. Indeed, sometimes it flatly contradicts proposed explanations for Y. Thus, we get clashing portraits of Joseph Smith as ignorant scholar, sincere deceiver and brilliant fool.
For most Latter-day Saints, probably, the best response remains to laugh — and then to get on with living and building the kingdom.