The core of a theory is that since Judaism is based on events witnessed by something like 3,000,000 Jews, it is true, while other religions rely on an individual or a few individuals who experienced a supernatural event that they then spread word of (which could be an uncheckable lie).
I was reading a portion of Kings II when I came to the life of King Josiah. According to the annotations of my ArtScroll Stone Edition Tanakh, there was a severe lack of Torah knowledge during this time because of what King Manasseh, Josiah's grandfather, had done. He had been bent on getting rid of all traces of Judaism from his society and filling it with idolatry. The Tanakh even says how the downfall of Judah into exile was directly caused by his actions. Not even Josiah's amazing attempts to right everything was enough. The Tanakh says there was no King like Josiah who followed the LORD with all his heart, soul and more. But that's getting ahead of myself.
The issue comes from what sparked this change in Josiah. When he was 8 years old, he began seeking the God of his forefathers (II Chronicles 34). When he was 12 he began purging the land of idols. When he was 18 he sent his scribe Shafan to the temple, and while there to take care of some business, Shafan received the scroll of the covenant (The Torah), which had been found by the high priest. Shafan read the scroll to Josiah, who then proceeded to rend his garments. He got word from a prophetess who said the punishment for Israel's misdeeds would come no matter what, but he still went and did his best to get rid of idolatry and return the Torah and Judaism to Judah.
So the potential issue here is, in the theory explained by Rabbi Kelemen above, one condition is that there is no person who fits as the seed who planted the Torah into the group of people who forgot who they were and became known as Jews.
He calls this person "Fred" in his article, just for example's sake. Here's an excerpt:
Fred could explain things, again with a smart (uncheckable) lie, claiming that God spoke to him alone and revealed the Torah’s long-lost text and the story of its original revelation at Mount Sinai. Indeed, most modern skeptics gravitate toward a theory like this.
A major problem with this theory is we’ve never heard of Fred or his heroic resurrection of Judaism. Certainly one of the most significant events in Jewish history would have been the fumble, when world Jewry forgot they were the three million prophets, and the recovery, when Fred reminded the Jews about the national prophecy at Mount Sinai. Yet in an otherwise comprehensive Jewish history we find no mention of such a claim.
He even mentions the issue of Josiah (Yoshiyahu):
(Occasionally people try to pin the title “Fred” on minor players like Hilkeyahu, Shafan, or Yoshiyahu. At best, such attempts are forced and ask the reader to interpret texts with crowbar and mallet in hand. They also require shamefully contrived rationalizations attempting to explain (a) why not one Biblical verse explicitly mentions the key point that the Jews forgot about the Torah and “Fred” reintroduced them to it, and (b) why the name of the second most important Jewish hero (next to Moses) appears in the Bible less often than the names “Pharaoh,” “Yeravam,” and “Haman.”)
I'm not sure that this sufficiently addresses the issue. Josiah is very obviously distressed and the scroll itself is obviously the Torah. (The section in II Chronicles directly says it's the Torah). Josiah began his fight against idolatry before he read the Torah, so he obviously knew that idolatry was forbidden. My guess is this was from an oral tradition. He sought God and found some answers. Then, when he read the source of it all and realized what the punishments for these sins were, he was distressed. He proceeded to gather all of Judah and Benjamin and read the scroll in front of them, making them accept the words again. In other words, it was like accepting the covenant again. This is what it seems like to me. The population was Torah ignorant and someone brought it to them again and had them accept it.
Josiah seems like someone who could fit in the "Fred" role.
I love this explanation for the truth of the Torah, but this issue has been bothering me for a while. If any of my fellow Jews can give any informed input, it would be appreciated.