There are many proofs that Joseph Smith was a false prophet, but Mormons will not accept them. Mormons trust a 'testimony' that Mormonism is the restored church & Joseph Smith its true prophet. 
SOCRATES TAUGHT HIS STUDENTS TO PURSUE TRUTH, QUESTION & ANALYZE ALL BELIEFS ONE HOLDS DEAR:

IF A BELIEF PASSED THE TEST OF EVIDENCE, DEDUCTION, & LOGIC, IT SHOULD BE KEPT

IF NOT, IT SHOULD NOT ONLY BE DISCARDED, BUT THE STUDENT MUST ALSO THEN QUESTION WHY ONE WAS LED TO BELIEVE THE ERRONEOUS BELIEF TO BEGIN WITH

What do the Experts say?

Joseph Smith copied three drawings from the Egyptian scrolls, labeled them Facsimile No. 1, No. 2, & No. 3, & incorporated them into the Book of Abraham with explanations of what they were.

Egyptologists have viewed the drawings & found Joseph Smith's interpretation of them to be wrong.

But, the Mormons, in defense of the sacred book, maintained that the Facsimiles alone were not sufficient to prove that Joseph Smith was erring in his translating abilities. With the rediscovery of the papyri, not only were they the same drawings as in the scrolls, but so was the text from which Joseph Smith made his translation.

It was now possible to absolutely determine the accuracy of Smith's translating abilities.

Facsimile No. 1

Joseph Smith said that Facsimile No. 1 was of a bird as the "Angel of the Lord" with "Abraham fastened upon an altar," "being offered up as a sacrifice by a false priest. The pots under the altar were various gods "Elkenah, Libnah, Mahmackrah, Korash, Pharaoh," etc.
In reality, this is "an embalming scene showing the deceased lying on a lion-couch."

In the original papyri, this drawing is attached to hieroglyphics [figure A below] from which Joseph derived the beginning of the book of Abraham which begins with the words, "In the Land of the Chaldeans, at the residence of my father, I, Abraham, saw that it was needful for me to obtain another place of residence"(1:1).

In reality, the hieroglyphics translate as, "Osiris shall be conveyed into the Great Pool of Khons -- & likewise Osiris Hor, justified, born to Tikhebyt, justified -- after his arms have been placed on his heart & the Breathing permit (which [Isis] made & has writing on its inside & outside) has been wrapped in royal linen & placed under his left arm near his heart; the rest of the mummy-bandages should be wrapped over it. The man for whom this book was copied will breath forever & ever as the bas of the gods do."
"It is the opening portion of an Egyptian Shait en Sensen, or Book of Breathings . . . a late funerary text that grew out of the earlier & more complex Book of the Dead." "This particular scroll was prepared (as determined by handwriting, spelling, content, etc.) sometime during the late Ptolemaic or early Roman period (circa 50 B.C. to A.D. 50)."

Figure A

Figure A is a professional reconstruction of the original (Figure B). Note the hieroglyphics on the right side from which Joseph Smith began his translation of the Book of Abraham.
In actuality, it "depicts the mythical embalming & resurrection of Osiris, Egyptian god of the underworld. Osiris was slain by his jealous brother Set, who cut up his body into 16 pieces & scattered them....The jackal-headed god Anubis is shown embalming the body of Osiris on the traditional lion-headed couch so that he might come back to life..."

Figure B

Figure B (to the right) shows a reprint of the actual papyrus used by Joseph Smith
Note the areas where the Papyrus has been lost. It is in these that Joseph Smith "finished" the drawing resulting in Facsimile No. 1. His restoration, according to Egyptologists, reveals a complete lack of understanding of Egyptian practice & theology.

Facsimile No. 2

As is explained by Joseph Smith & included in the Pearl of Great Price, the second drawing contains different scenes which Joseph Smith interpreted. They vary: "Kolob, signifying the first creation, nearest to the celestial, or the residence of God." "Stands next to Kolob, called by the Egyptians Oliblish, which is the next grand governing creation near to the celestial or the place where God resides." "God, sitting upon his throne, clothed with power & authority." "...this is one of the governing planets also, & is said by the Egyptians to be the Sun, & to borrow its light from Kolob through the medium of Kae-e-vanrash, which is the grand Key..."
But again scholarship disagrees with Joseph's rendition. 'It is actually a rather common funerary amulet termed a hypocephalus, so-called because it was placed under (hypo) a mummy's head (cephalus). Its purpose was to magically keep the deceased warm & to protect the body from desecration by grave robbers."

Facsimile No. 3     

According to Smith, this drawing shows 'Abraham sitting upon Pharaoh's throne, by the politeness of the king, with a crown upon his head, representing the Priesthood...King Pharaoh, whose name is given in the characters above his head...Signifies Abraham in Egypt...Olimlah, a slave belonging to the prince...'
But this is not what the Egyptologists say is the meaning of the Facsimile No. 3 is. Instead, it shows, "the deceased being led before Osiris, god of the dead, & behind the enthroned Osiris stands his wife Isis."

It should be quite obvious that present scholarship has revealed that Joseph Smith did not translate the Book of Abraham by the power of God as he had claimed.

It follows that if he did not translate the Book of Abraham by the power of God, then it would be very easy to conclude that he did not translate the Book of Mormon by the power of God either.

When Joseph first gave his translation, hieroglyphics were undecipherable. Today they are.

He was safe in saying anything he wanted to & there would be no way of proving him wrong. But with the resurfacing of the same papyri he used to do his Book of Abraham translation, & the fact that he did not in any way do it correctly, should be proof enough that Joseph Smith lied about his abilities from God.

He has been shown to be a false prophet.

to repeat, obviously Egyptologists have revealed that Joseph Smith did not translate the Book of Abraham by the power of God as he had claimed & thus, nor did he translate the Book of Mormon by the power of God - & as such, if such an angel as Moroni existed, it could only have come from Satan.

Joseph Smith also made the following false prophesy about the United States [obviously it never happened] - History of the Church, vol. 5, p. 394, May 1843

Jesus got married & had children

The true gospel was lost from the earth. Mormonism is its restoration, Articles of Faith, by James Talmage, p. 182-185

There is no salvation without accepting Joseph Smith as a prophet of God, Doctrines of Salvation, Vol. 1, p. 188

The book of Mormon is more correct than the Bible, History of the Church, 4:461

If it had not been for Joseph Smith & the restoration, there would be no salvation.  There is no salvation [the context is the full gospel including exaltation to Godhood] outside the church of Jesus Christ of Latter-day Saints, Mormon Doctrine, p. 670.

There are many gods, Mormon Doctrine, p. 163

There is a mother god, Articles of Faith, by James Talmage, p. 443

There are three levels of heaven: telestial, terrestrial, & celestial, Mormon Doctrine, p. 348

The Holy Ghost is a male personage, A Marvelous Work & A Wonder, by Le Grand Richards, Salt Lake City, 1956, page 118; Journal of Discourses, Vol. 5, page 179 

Mormonism demands:

pay a full 10% tithe to the Mormon church

follow various laws & ordinances of the church  [At this point, they receive a temple recommend whereupon, the Mormon is allowed to enter their sacred temples in order to go through  set of secret rituals: baptism for the dead, celestial marriage, & various oaths of secrecy & commitment].

4 secret handshakes are taught so the believing Mormon, upon entering the third level of Mormon heaven, can shake hands with God in a certain pattern. This celestial ritual is for the purpose of permitting entrance into the highest level of heaven;  & exaltation to godhood awaits those who achieve this level - then, he [maybe she] will be permitted to have his own planet & be a god of his own world;  thus the Mormon system will be expanded to other planets. I kid you not!

1 Ne. 1:2, etc., states that Hebrews who left Jerusalem & came to the Americas spoke Egyptian.

It is a known fact that Hebrews spoke Hebrew, & their records were kept in Hebrew. Egyptians were their enemies. It is as absurd to think that Hebrews would have written their sacred history in Egyptian as to think that American History would have been written in Russian

In Mormon 9:32, 34, it states that the language was "reformed Egyptian" & that no other people knew their language.

There is no known language called "reformed Egyptian"

1 Ne. 18:1 talks about ample timber that Jews used to make a ship.

There is not ample timber in that area. It was a desert; it still is a desert.

1 Ne. 2:6-9 mentions a river named Laman that flows into the Red Sea.

There is no river there & there has not been since the Pleistocene era.

Botanical problems are many in the Book of Mormon. Wheat, barley, olives, etc., are mentioned,

none of these were in the Americas at that time. North America had no cows, asses, horses, oxen, etc. Europeans brought them many hundreds of years later. North America had no lions, leopards, nor sheep at that time. Honey bees were brought here by Europeans much later.

Ether 9:18, 19, lists domestic cattle, cows & oxen as separate species!

Again they did not even exist in the Americas at that time.

The Book of Mormon also mentions swine as being useful to man.

Maybe, but Jews would not think of swine as being useful or good; swine were forbidden, unclean animals to the Jews.

Ether 9:30-34 talks about poisonous snakes driving sheep to the south. The Book of Mormon tells that the people ate the snake-killed animals, all of them! (v. 34).

Jewish people could not have eaten animals that were killed that way, since Mosaic law forbids it!

Chickens& dogs did not exist here at that time either.

3 Ne. 20:16 and 21:12 talk about lions as "beasts of the forests."

Lions do not live in forests or jungles, & they never lived in the Americas.

No silk and wool clothing [nor moths] existed, as 1 Ne. 13:7; Alma 4:6; Ether 9:17 and 10:24 indicate, at that time either.

Butter is also mentioned, but could not possibly exist, since no milk-producing animals were found in the Americas at that time.

Ether 15:30-31 says that after Shiz was beheaded, he raised up & struggled for breath?

In Ether, chapter 6, we learn that furious winds propelled the barges to the promised land for 344 days!

Even if the winds were not "furious," but, for example, blew only 10 miles per hour, the distance traveled in 344 days would have been 82,560 miles, or more than three times around the world.

When Lehi left Jerusalem, according to the Book of Mormon, his group consisted of fewer than 20 people. Yet 19 years later the people had so prospered & multiplied in the promised land that they built a temple which "manner of construction was like unto the temple of Solomon: & the workmanship thereof was exceeding fine" [2. Ne. 5:16].

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