score:4
(I will address various parts of the OP's questions in separate posts, for readability)
Depperm's post on this question makes an effective case in favor of the credibility of the Book of Mormon witnesses, and offers a veritable treasure trove of links for further reading. I'll offer 3 distinct positive arguments for their reliability.
1. Quitting a job because of a frustrating manager
5 of the 11 witnesses never left the church (Joseph Smith Sr, Hyrum Smith, Samuel Smith, Christian Whitmer, Peter Whitmer Jr.)
6 of the 11 witnesses did leave the church (Oliver Cowdery, David Whitmer, Martin Harris, Jacob Whitmer, John Whitmer, Hiram Page)
2 of the 6 who left later came back (Oliver Cowdery, Martin Harris)
0 of the 11 ever denied their testimony of the Book of Mormon, despite several having great incentive to do so
They say people don't quit jobs; they quit managers. There is a useful analogy to be drawn here to the Book of Mormon witnesses.
The 6 witnesses who left the church did so in large degree because of a falling out with Joseph Smith (this is not to say Joseph Smith was a bad manager, but he was human). The failure of the Kirtland Safety Society (KSS) during the Panic of 1837 played a role in these deteriorating relationships (I discuss the KSS in more detail in this post). So did pride--David Whitmer did not respond well when he was called upon to repent (see here).
With this in mind, let's apply the "quitting a job" analogy to consider motives/incentives.
If I quit a job because I cannot stand my manager--or perhaps more generally, I just have issues with the company's leadership--what sorts of things am I likely to say about that company down the road? You may have met people whose departure from an employer was unpleasant (I certainly have) -- ever hear them speak glowingly of the company?
Why in the world then would the witnesses who left the church--several of whom had biting comments to make about Joseph Smith--speak so forcefully, consistently, and relentlessly in favor of the authenticity of the Book of Mormon? They were the single most well-placed individuals (esp. Oliver Cowdery) to annihilate Joseph Smith's reputation and credibility by denouncing the Book of Mormon (which Joseph Smith called "the keystone of our religion") and yet, not only did none of them ever denounce the Book of Mormon, they didn't stay quiet either: they spoke actively and repeatedly in favor of the book.
This is not something we should expect--this is contrary to human nature.
It gets better. Oliver Cowdery & Martin Harris left the church, but in later years came back. They received no prominent church leadership position for doing so. No one knew better the details of the coming forth of the Book of Mormon than Joseph Smith & Oliver Cowdery--if there was a fraud, Cowdery didn't just know about it, he was in on it.
It may be worthwhile to reflect on how humiliating it would be for someone like Cowdery (or Harris) to come back, tail between their legs, and admit very publicly "I was prideful; I was wrong; I never should have left". Both had a wife/in-laws who were opposed to the church. Both came back when Brigham Young was leading the church. Brigham Young is called in Latter-day Saint folklore "the lion of the Lord"--he could chastise like none other. You didn't go admit an embarrassing failure to Brigham Young lightly.
Back to the job analogy. So now our protagonists have left the job and it was an awful break-up. They have the power to publicly destroy the company and decline to use it. Their families want them to have nothing to do with the company. And then two of them--both of whom used to be "executives" at the company--ask the hard-spoken, intimidating new CEO, if they can come back and work a rank-and-file position. Say what???
Oliver Cowdery & Martin Harris's actions--and the humiliation they put themselves through--are senseless unless they sincerely believed it was the right thing to do.
Denouncing the Book of Mormon would have resulted in praise by their neighbors (the witnesses who left the church no longer lived among church members), whereas holding to their testimonies cost them dearly. Yet all the peer pressure in the world could not get them to crack.
I propose that there is one and only one clear, viable explanation for their behavior: their testimonies were sincere. The witnesses were not perfect men, but they were men of integrity, even when it was costly to be so.
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2. David Whitmer was a Theist
This argument could be made of other witnesses too--to be concise we'll just run it for David Whitmer.
The following statements of David Whitmer, the last surviving of the 3 witnesses, are worth repeating:
David Whitmer lived outside the Church for 50 years following his excommunication—never to return but never to deny his testimony. As the last surviving Witness, he was often interviewed—and often misquoted. To one man who claimed that David had recanted his testimony, he declared:
“That he may understand me now, if he did not then; and that the world may know the truth, I wish now, standing as it were, in the very sunset of life, and in the fear of God, once for all to make this public statement:
“That I have never at any time denied that testimony or any part thereof, which has so long since been published with that Book, as one of the three witnesses.”
A year before his death in Richmond, Missouri, David responded to two encyclopedias that claimed he and the other Witnesses had denied their testimonies of the Book of Mormon.
He declared: “I will say once more to all mankind, that I have never at any time denied that testimony or any part thereof. I also testify to the world, that neither Oliver Cowdery or Martin Harris ever at any time denied their testimony. They both died affirming the truth of the divine authenticity of the Book of Mormon.” (source)
To paraphrase Dickens, David Whitmer believed in God. This must be distinctly understood, or nothing wonderful can come of the comments I am going to relate.
For a god-fearing Christian to declare on his deathbed something that, if false, would not only stain his loved one's reputation for all time, but mark him a blasphemer in open rebellion against Almighty God, is pretty gutsy.
As David Whitmer prepared to meet his Maker, the prospect of giving an accounting to God would have loomed large next to the fading pressures of this world. Why would he testify of the Book of Mormon at this time? I suggest the simplest solution--by far--is that the prospect of standing before God having denounced what the voice of God had told Him to be true scared the hell out of him.
(I'm not cussing, I mean that quite literally)
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3. Why do we trust God's witnesses, past or present
On this question's opposite number, I offered 3 reasons why Christians trust the testimony of the original apostles (or at least 11 of them--can't say I've ever heard Iscariot quoted at church):
I propose identical criteria here for evaluating the Book of Mormon and those who brought it to the world.
a. Their fruits
If the early leaders of The Church of Jesus Christ of Latter-day Saints did not sincerely believe their story, the meteoric rise of the faith--in spite of intense opposition--is very difficult to explain.
In this post I briefly outlined some of the costs/persecutions Joseph Smith and his family endured for sticking to their story.
The book Saints offers historians' insights on the sufferings & perseverance of the Smiths and numerous other early church members.
For a look at some of the more contemporary fruits--the actions and results of the church whose doctrine is anchored to the Book of Mormon--I recommend this sermon by a member of the church's General Relief Society Presidency, Sharon Eubank.
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b. Their willingness to die
Joseph Smith and his brother Hyrum (one of the 8 witnesses) gave their lives for their faith, leaving wives and young children behind them.
A confession that it was all a hoax could have bought them their freedom. A focus on power could have given them an army to protect them from Thomas Ford (see here). They did not deny, they did not run away, and they did not engage in siege warfare with the Governor or Illinois to save their skin:
like most of the Lord’s anointed in ancient times, [Joseph] has sealed his mission and his works with his own blood; and so has his brother Hyrum. (statement by John Taylor who was present when they died, see here)
From Elder Jeffrey R. Holland, one of the present day apostles of The Church of Jesus Christ of Latter-day Saints:
When Joseph Smith and his brother Hyrum started for Carthage to face what they knew would be an imminent martyrdom, Hyrum read these words to comfort the heart of his brother:
“Thou hast been faithful; wherefore … thou shalt be made strong, even unto the sitting down in the place which I have prepared in the mansions of my Father.
“And now I, Moroni, bid farewell … until we shall meet before the judgment-seat of Christ.”
A few short verses from the 12th chapter of Ether in the Book of Mormon. Before closing the book, Hyrum turned down the corner of the page from which he had read, marking it as part of the everlasting testimony for which these two brothers were about to die...
In this their greatest—and last—hour of need, I ask you: would these men blaspheme before God by continuing to fix their lives, their honor, and their own search for eternal salvation on a book (and by implication a church and a ministry) they had fictitiously created out of whole cloth?
Never mind that their wives are about to be widows and their children fatherless. Never mind that their little band of followers will yet be “houseless, friendless and homeless” and that their children will leave footprints of blood across frozen rivers and an untamed prairie floor. Never mind that legions will die and other legions live declaring in the four quarters of this earth that they know the Book of Mormon and the Church which espouses it to be true. Disregard all of that, and tell me whether in this hour of death these two men would enter the presence of their Eternal Judge quoting from and finding solace in a book which, if not the very word of God, would brand them as imposters and charlatans until the end of time? They would not do that! They were willing to die rather than deny the divine origin and the eternal truthfulness of the Book of Mormon.
For 179 years this book has been examined and attacked, denied and deconstructed, targeted and torn apart like perhaps no other book in modern religious history—perhaps like no other book in any religious history. And still it stands. Failed theories about its origins have been born and parroted and have died—from Ethan Smith to Solomon Spaulding to deranged paranoid to cunning genius. None of these frankly pathetic answers for this book has ever withstood examination because there is no other answer than the one Joseph gave as its young unlearned translator. In this I stand with my own great-grandfather, who said simply enough, “No wicked man could write such a book as this; and no good man would write it, unless it were true and he were commanded of God to do so.” (see here)
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c. The witness of the Holy Spirit
From the final chapter of the Book of Mormon:
And when ye shall receive these things, I would exhort you that ye would ask God, the Eternal Father, in the name of Christ, if these things are not true; and if ye shall ask with a sincere heart, with real intent, having faith in Christ, he will manifest the truth of it unto you, by the power of the Holy Ghost. (Moroni 10:4)
I conclude by echoing what millions before me have affirmed: I have received that witness.
Upvote:0
"And we lie not, God bearing witness of it"
God bears witness of the truthfulness of the Book of Mormon to all who ask Him in faith as outlined in chapter ten of Moroni, third through fifth verses.
Anyone who fails to do this or who chooses not to exercise faith is building his house (or in other words, his entire existence) on a knowledge base or a foundation made of sand. Those dubious theories and skeptical tools are that foundation of sand. They change every year. Anybody who sticks around for more than a few and who doesn't have the problem of wishful forgetting will see that this is true.
The Book of Mormon is the foundation of rock. No one who builds on it will ever fall.
The floods and the rains are coming in fast. There is not much time left to build.
Upvote:4
(I will address various parts of the OP's questions in separate posts, for readability)
The belief that Joseph Smith introduced a new version of Jesus
The commonly cited passage is Galatians 1:8:
But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed.
This does not engage with the views of Latter-day Saints, who believe that Jesus restored truth through the Prophet Joseph Smith that had been lost through apostasy. The very doctrine of The Church of Jesus Christ of Latter-day Saints requires that its teachings differ from existing, 1820 Christian faith: if there were no substantial change in doctrine there would be no need for a restoration!
This argument then is akin to telling Martin Luther his Theses must be wrong because he's preaching another gospel than the prevailing early 16th century teachings of the Catholic Church.
As a Latter-day Saint, I take no issue with the Biblical teachings on Jesus. I do, however, take exception to the creeds developed in councils in the 4th & 5th centuries.
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Plagiarism from the King James Bible
My thoughts are presented in section 1B here
Cliff-notes version:
There is a fundamental difference in the understanding of scripture that leads the LDS to see this issue very differently from many of other faiths. We do not have a doctrine of scriptural inerrancy, and as a result, textual criticism & seeking out an Ur-text are less central to our theology, which is rooted in modern revelation. As a result—and I know that this is frustrating to many of other faiths—we aren’t bothered by the possibility that a minor historical detail is misstated, as long as the doctrinal message of the passage is preserved.
I believe a good but imperfect translation can be adequate for God’s purposes—He’s willing to work through His human servants, even if their writing isn’t as good as His. Specifically, I suggest Joseph Smith was inspired to use words he knew--my own experience with revelation supports this--rather than taking on an entirely different literary persona. As one who has done some translation, I can confirm that two translators who have a different vocabulary can produce distinct translations that both convey the message.
The words of the King James Bible would have been words well-known to Joseph Smith.
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Reformed Egyptian
We should expect to find writing (and we do!) in Mesoamerica - but not Egyptian writing. The Book of Mormon itself indicates that Reformed Egyptian was not the preferred form of writing (see Mormon 9:33), and was only used on the plates due to space constraints. The record-keeping discussed in the book implies relatively few were taught the language and regular religious communication neither used plates (impractical) nor Egyptian (unnecessary). A lesser-known language such as this would have no practical value in everyday commerce or in public inscriptions.
The fact that the language is not known from any other civilization is expressly acknowledged by the text in Mormon chapter 9:
32 And now, behold, we have written this record according to our knowledge, in the characters which are called among us the reformed Egyptian, being handed down and altered by us, according to our manner of speech.
…
34 But the Lord knoweth the things which we have written, and also that none other people knoweth our language;
It is also noteworthy that the existence of writing in Mesoamerica shows up in the archeological record during the time and place covered by the Book of Mormon. The idea that writing was introduced to the Americas by the Old World is extremely consistent with the Book of Mormon. The idea that writing—arguably humanity’s most brilliant invention—was developed independently but along similar lines in both the Old World and the New is not impossible, but it would be a greater miracle than most of the claims in the Bible or the Book of Mormon!
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Theosis
I have written on Theosis & the Nature of God here and produced a brief video on the subject here. See also Depperm's answer on this site here.
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Edits to the Book of Mormon
There are two intense ironies that this argument regularly resurfaces for air.
If the fact that scribal errors were made in copying the Book of Mormon text were evidence of the Book of Mormon's non-Divine origin, this would be much, much, much, much, much more problematic for the Bible. I've written separately on the Hermeneutics site defending the text of the Bible through the lens of textual criticism.
What are these numerous changes that were made to the text??? (this part always gets left out when critics raise the topic).
The overwhelming majority of the textual variations in the Book of Mormon are traceable to one handwritten manuscript, known as P.
Most of the original Book of Mormon manuscript (O) was destroyed by water in the 19th century -- the first copy that was made (P) is essentially fully extant, and it contains known copyist errors. Subsequent editions of the book have sought to correct the errors perpetuated by P, which was the source used for early Book of Mormon printings in both the US & England (printing plates from England enabled the first mass production of the Book of Mormon, but the plates were created using a text that relied on manuscript P).
Like most of the 400,000 known New Testament variants, most of the variants from P (and its descendants) are not theologically material. There's a handy O vs. P summary here.
As noted by Depperm previously, when Joseph Smith listed himself as the author and proprietor in the first edition he did so for copyright reasons, not because he was the author; later editions clarified this.
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Grammar in the Book of Mormon
See section above on the use of the King James Bible. Here again, the translation was relayed through Joseph Smith using his own vocabulary. This is in fact supported by the testimony of his scribes, who noted that when he came to a proper name (e.g. Nephi, Zarahemla) he didn't know, he would spell it out for the scribe.
That the 1829 translation uses the English language of 1829 & the language of the era's most widely circulating piece of literature (KJV) is to be expected! The translation is a rendering in English and does indeed use English words that didn't exist 2000 years ago to convey ideas as they were recorded in the original language (there was no English language 2000 years ago).
Because modern English has been influenced by German, French, Latin, Greek, etc., a translation into 1829 English will bear the influence of these languages as well.
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Conclusion
It is true that The Book of Mormon does not look like the text a believer in Biblical inerrancy or plenary verbal inspiration would expect. Latter-day Saints do not believe in Biblical inerrancy nor that every word in scripture is the product of plenary verbal inspiration. Rather, we have a distinct view on revelation that differs from that of the Protestant Reformation.
While many questions can be raised with respect to the historicity of the Book of Mormon account (my responses to the most popular arguments here), none of those addressed in the twin question directly impeach the credibility of the 3 & 8 witnesses.
Disclaimer: these viewpoints are the product of my own study and do not constitute official statements by The Church of Jesus Christ of Latter-day Saints.
Upvote:8
(I will address various parts of the OP's questions in separate posts, for readability)
For about 50 years in the 19th century the Spaulding manuscript was the most popular naturalistic explanation for the origin of The Book of Mormon; it has now been widely discredited by both friends and foes of The Book of Mormon.
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Background on the manuscript
(summarized from Rex C. Reeve Jr.’s What is “Manuscript Found”? as published in Manuscript Found: The Complete Original “Spaulding Manuscript” available online here)
Solomon Spaulding wrote a document entitled “Manuscript Found”, which has some loose similarities with the Book of Mormon (e.g. a group of people crossed the ocean and settled the Americas, they became divided, they fought wars, their record was discovered many years later); from his own correspondence we know he was working on the manuscript in 1812.
Spaulding died in 1816 without having ever completed or published the manuscript. The manuscript remained in the possession of his family until the 1830s.
In 1833 Philastus Hurlbut was excommunicated from The Church of Christ (now known as The Church of Jesus Christ of Latter-day Saints) for sexual immorality. He had previously served as a missionary for the church but, in his anger, turned hard against the church and sought to tear it down. His efforts included:
(Hurlbut’s later criminal actions and flight from the US to escape justice only further assassinated his character).
Hurlbut heard of Spaulding’s work from people who had known him, and saw an opportunity to discredit The Book of Mormon by claiming it was stolen from Spaulding’s work. Hurlbut acquired the Spaulding manuscript from Spaulding’s family in 1833 or 1834.
Because Hurlbut was not a publicly credible source (see above), he couldn’t publish his theory in his own name–he sold the documents to E.D. Howe and Howe used them to publish his hit-piece Mormonism Unvailed [sic], released in 1834.
Neither Hurlbut nor Howe released the Spaulding manuscript publicly–and for good reason–it would allow readers to check the story for themselves. Howe sold the papers to L.L. Rice circa 1839 and the Spaulding manuscript disappeared for several decades. This was convenient for conspiracy theorists, who could imagine the text to have said anything they wanted. Affidavits were secured (by Hurlbut) from enemies of Joseph Smith stating that The Book of Mormon borrowed numerous features from the Spaulding manuscript.
Research published by George Reynolds in 1883 indicated that Hurlbut knew full well the Spaulding manuscript was unrelated to The Book of Mormon. Hurlbut (the mastermind of the plan) had stated:
I obtained a manuscript... which was reported to be the foundation of the ‘Book of Mormon’ ... when upon examination I found it to contain nothing of the kind, but being a manuscript upon an entirely different subject. (The Myth of the "Manuscript Found," or the Absurdities of the “Spaulding Story" p. 17)
However, the manuscript was rediscovered among Rice’s papers in 1884, and has been thoroughly studied in the years since. With the rediscovery of the manuscript it became abundantly obvious that there was no literary relationship between the Spaulding text & The Book of Mormon, and Hurlbut had vastly overstated their similarities–the affidavits were thereby demonstrated to be fraudulent.
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The texts can readily be compared
Although some continue to claim a literary relationship between the Spaulding manuscript & The Book of Mormon, there's one thing virtually all these claimants have in common: they haven't read both documents.
There is no need to take someone else’s word for it–those who are curious can readily compare them–both are available for free online:
Spaulding manuscript & The Book of Mormon
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The Value of Hostile Testimony
Even professional critics of The Book of Mormon acknowledge that the Spaulding theory is bankrupt. The following quotations (and others) were assembled by Reeves (see link above pp. xx-xxiii) from anti-Mormon sources--here is a brief survey covering more than a century of scholarship in which testimony hostile to The Book of Mormon rejects the Spaulding theory:
From Davis H. Bays in 1897:
The usual debater undertakes to trace the Book of Mormon to the Spaulding romance through Sidney Rigdon.
Nothing can be more erroneous, and it will lead to almost certain defeat. . .. In order “for” the successful refutation of the Mormon dogma it is not at all necessary to connect Sidney Rigdon with Joseph Smith in its inception. In fact, such a course will almost certainly result in failure; and the principal reason why it will fail is because it is not true. ...
The long-lost Spaulding story has at last been unearthed, and is now on deposit in the library of Oberlin College at Oberlin, Ohio, and may be examined by anyone who may take the pains to call on President Fairchild, of that institution.
... The writer has examined a certified copy of this remarkable document, and to say he was surprised is to express it moderately. Instead of exhibiting the qualities of a scholarly mind, as we had been lead to believe it would do, quite to the contrary, it bears every mark of ignorance and illiteracy, and is evidently the product of a mind far below the average, even in the ordinary affairs of life. A twelve-year-old boy in any of our common schools can tell a better story and couch it in far better English. The Spaulding story is a failure. Do not attempt to rely upon it—it will let you down.
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From Ernest H. Taves in 1984:
The evidence, then, indicates that this Spaulding manuscript had nothing to do with the Book of Mormon. In that case, how are we to account for the Hurlbut affidavits?
It has been suggested that there was another Spaulding work, that the manuscript Hurlbut unearthed was not what everyone was referring to as Manuscript Found. This is, of course, a possibility, but the question might seem, at first glance, irrelevant. If there was another Spaulding manuscript would it not be stylistically similar to the one Hurlbut found, and thus have little in common with the Book of Mormon? Only a skillful writer indeed—a gifted parodist, for example—can significantly alter his way of writing. The signature is there, as with a thumbprint. Whatever else can be said of Joseph Smith and Solomon Spaulding, neither was a skillful writer. It suffices to read a page or two of Joseph Smith and of Spaulding to understand that those pages were written by different writers. The same would probably apply to any other manuscript written by Spaulding. ...
This still leaves us with questions about the affidavits. How could they be so far off the mark? First, we must agree with Brodie that they were written by Hurlbut—and here we again invoke stylistic considerations. The affidavits have the tone of common authorship. Further, there is the almost universal insistence upon the “and it came to pass” phraseology, and upon the proper names of Nephi and Laman. Hurlbut put thoughts into the minds of his respondents, and words into their mouths.... One would like to know more of Hurlbut here. We must suspect that he was not without his own manipulative abilities as he pursued what he was after. He was grinding an important ax, and his respondents were certainly also motivated: The manuscript of their brother, relative, and friend had been plagiarized—in what they considered to be a blasphemous cause—and they would have vengeance. So they remembered what Hurlbut suggested, thus giving birth to the Spaulding-Rigdon theory four years after Joseph had completed his manuscript.
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Additional anti-Mormon quotes rejecting the Spaulding theory can be found here, including Fawn Brodie’s classic statement in 1945:
The tenuous chain of evidence accumulated to support the Spaulding-Rigdon theory breaks altogether when it tries to prove that Rigdon met Joseph Smith before 1830.
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Second manuscript theories
(see also Reeves link above)
After the Spaulding manuscript was rediscovered and the theory collapsed, some sought to revive the theory by claiming that there was a second manuscript (maybe a revised version of the original, a sequel, etc.) and that it was this second edition that was referred to in the Hurlbut affidavits and used by Joseph Smith. Second manuscript theories are entirely unsubstantiated by the evidence:
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Other problems with the Spaulding theory
Sidney Rigdon
Even the most ardent 19th century proponents of the Spaulding theory acknowledged that the Book of Mormon could not be an exact copy of Spaulding’s work, but must have been through a major revision. The relatively uneducated Joseph Smith was not seen as a promising candidate for having revised Spaulding’s work, and theorists (generally) concluded that Sidney Rigdon was the most likely individual to have conspired with Joseph Smith to revise & publish the manuscript.
This view collapses quickly under scrutiny:
Even if Sidney Rigdon had managed to acquire the Spaulding manuscript (an argument that is entirely ad-hoc), there was no way for him to get it to Joseph Smith. He had no interaction with The Book of Mormon until after it was published.
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Stylometric analysis
(Drawn from Book of Mormon Authorship – New Light on Ancient Origins)
Stylometry studies word-prints and offers a means of determining who wrote an anonymous text. Like a fingerprint, people leave traceable patterns in their writing. Very small samples (e.g. a few verses) are insufficient for statistically-significant stylometric analysis, but longer passages are quite relevant and the scientific apparatus is well-studied. Stylometry has been used to determine authorship of a variety of documents, including some of the Federalist Papers.
An author’s word-print has been shown to survive translation, and authors who try to game the system and mimic another author’s style have been betrayed by their own unconscious writing habits—stylometry can catch the ruse. Even when an author has multiple characters who speak and behave differently, the author’s word-print can be discerned.
The Book of Mormon has been subjected to stylometric analysis which has demonstrated, among other things:
Regardless of how many manuscripts we hypothesize that Spaulding wrote, his literary fingerprint can be discerned from his known writings, and it does not match that of the Book of Mormon text.
Conclusion
There will always be someone willing to write a sensational story, but in the academic literature–on both sides of the aisle–the Spaulding conspiracy has long-since been recognized as fiction.
Upvote:11
Witnesses:
Testimony of Prophet Joseph Smith
declared an angel of God appeared to them and showed them the Book of Mormon plates and they heard the voice of the Lord pronounce that Joseph Smith’s translation had been accomplished “by the gift and power of God.” This experience took place in June 18291
declared that Joseph Smith himself showed them the plates and allowed each to “heft” the ancient artifact and examine its engravings. Several others had direct experiences with the plates or otherwise witnessed Joseph Smith’s translation of the Book of Mormon.1
Other witnesses1 (to varying extents, mainly feeling weight/shape):
Why should we believe them?
These witnesses testify of additional scripture, more direction and guidance from prophets and another witness to Jesus Christ. The bible is amazing, wouldn't having more scripture be just as or more amazing?
1 This is the third time I am coming to you. In the mouth of two or three witnesses shall every word be established.
To what extent are they credible?
All the witnesses concur on the description of the golden plates. Their witness are consistent throughout the remainder of their lives.
What are the strongest arguments for their credibility?
All of the Three Witnesses and three of the Eight Witnesses left the Church in 1838 and were hostile, at least for a time, against Joseph Smith. Yet, they clung to their witness and continued to affirm it.2
I enquired seriously at David if it was true that he had seen the angel, according to his testimony as one of the witnesses of the Book of Mormon. He replied, as sure as there is a God in heaven, he saw the angel, according to his testimony in that book. I asked him, if so, how did he not stand by Joseph? He answered, in the days when Joseph received the Book of Mormon, and brought it forth, he was a good man filled with the Holy Ghost, but he considered he had now fallen. I interrogated Oliver Cowdery in the same manner, who answered me similarly.
As to the Book of Mormon, it would be doing injustice to myself, and to the work of God of the last days, to say that I could know a thing to be true in 1830, and know the same thing to be false in 1847
It may not be amiss in this place, to give a statement to the world concerning the work of the Lord, as I have been a member of this church of Latter Day Saints from its beginning; to say that the book of Mormon is a revelation from God, I have no hesitancy; but with all confidence have signed my named to it as such; and I hope, that my patrons will indulge me in speaking freely on this subject, as I am about leaving the editorial department. Therefore I desire to testify to all that will come to the knowledge of this address; that I have most assuredly seen the plates from whence the book of Mormon is translated, and that I have handled these plates, and know of a surety that Joseph Smith, jr. has translated the book of Mormon by the gift and power of God, and in this thing the wisdom of the wise most assuredly has perished: therefore, know ye, O ye inhabitants of the earth, wherever this address may come, that I have in this thing freed my garments of your blood, whether you believe or disbelieve the statements of your unworthy friend and well-wisher.
In regards to skepticism mentioned by OP, not many of these are about the witnesses but more about the Book of Mormon, later revelation, or other matters (should probably be a separate question IMO)
Additional resources:
1 Witnesses of the Book of Mormon, Four Women were Witnesses to Book of Mormon Translation Process
2 FAIR: Did the witnesses who left the Church continue to maintain their witness of the Book of Mormon? not an official LDS source, but an apologist site. It does nicely compile and document many of the arguments/defenses surrounding the witnesses; official LDS source (I don't cite specifically, similar content) Witnesses of the Book of Mormon