How can we be sure that Judaism is true/the truth?

Question

I borrowed (with permission) a question from Ahmed Han, which is:

People of every religion claim that they are the ones in the right path. Even the people of sects in these religions think that they are on a better path than the peoples of other sects are on. How come could they be so sure?

As a Muslim, how can I be sure that my religion or sect/madhab/path is the rightful one? How can I be sure that there isn't any other religion sent by Allah which is better than Islam, but it is wrongly advertised so that I think that it is wrong?

Change some words and we get:

People of every religion claim that they are the ones in the right path. Even the people of sects in these religions think that they are on a better path than the peoples of other sects are on.

As someone who believes in Judaism, how can you be sure that the religion is the rightful one? How can I be sure that there isn't any other religion sent by God which is better than Judaism, but it is wrongly advertised so that I think that it is wrong?

Answer 1

This is really the most fundamental and important question on this site. But in my opinion, the other answers here have not done this justice by any stretch. They make it seem simple, and they may make us feel good, that we're really right, but in reality it's not so easy to show why Judaism is true, let alone prove it with certainty to "be sure" Judaism is true. They have presented more or less one-sided arguments and books, and while that is part of the puzzle, we'd be fooling ourselves to pretend that that is sufficient for determining the truth of any controversial question. One-sided arguments can just as well be presented on the Islam or Christianity SE sites, and while such an approach might satisfy some people, I don't think you'd be inclined to say that it gets them any closer to the truth.

Any answer going to the heart of determining a religion's truth is going to need to come from a neutral perspective. Before any evidence is considered, that really is the only position that makes sense: There are thousands of religions, each with firm believers. So nobody, Jews included, should start with a biased impression that they lucked out and were born into the right faith. The basic answer is going to need to explain how much evidence in favor of Judaism would be sufficient to justify belief in the faith and then examine what evidence there is. With that, this answer will attempt to approach the question from a rationalist perspective.

How much evidence is needed

For many things in life, not that much evidence is needed to believe something. You can tentatively believe that your generally honest friend had waffles for breakfast going on their casual word alone, because there's nothing extraordinary about his claim. If a stranger tells you he just ate a giraffe sandwich though, you'd probably need an explanation for how he obtained such rare meat along with some good reason to believe him like photographic evidence. If an Ancient Roman tells you that he saw Romulus ascend to heaven and he has a whole crowd of witnesses to prove it, you'd need to do some thorough cross examination of that crowd, and even if it checks out many people would remain skeptical. For Judaism, it is more equivalent to the latter cases. Although for some of us who were raised in a Jewish environment it may not seem like a particularly extraordinary claim, from the perspective of a person that doesn't already believe, they may need this higher level of evidence. For an outside observer, it can come off as an extraordinary claim that a given religion is true and that stories of supernatural events did happen and that the Jewish people had the unique ability to properly maintain stories without modification over a hundred generations, particularly since it is controversial in the sense that secular people have their own arguments against it. So a reasonable response to those arguments along with substantial evidence or reasoning is what is needed to be sufficiently confident that Judaism is true.

I'll bring up some of the more significant challenges to Judaism and how they might be resolved, and I will discuss the more popular arguments in favor of Judaism and where they might fall short. And so while this answer won't definitively prove Judaism true, I hope it will be useful to help people make that determination for themselves.

Arguments against Judaism and responses

Natural and early history according to the Torah appears wrong

One of the tougher challenges to Judaism I've seen basically argues that the Torah errs in describing early history, especially in the first 11 chapters of Genesis describing creation, the flood, and the development of language. For example, the scientific evidence indicates that the universe and Earth are older than 6000 years, that Noah's flood never occured, and that human history predated Adam and was not interrupted by Noah's flood. It is not a strong position, and possibly theologically unsound to dismiss the meaning, especially as it is understood as literal in various places in the Talmud. Further, the Torah records specific genealogies dependent on the historicity which are not well suited for allegorizing. Some Rishonim such as the Meiri also prohibit interpreting the story of creation as allegory, as discussed in this Machzikei HaDas essay on the varying opinions regarding allegorical interpretation of scriptures. Non-literal meanings are also made tenuous by the writings of other Rishonim, such as Rambam who says that it is a fundamental principle of the Torah that Adam was the first human created and that the genealogies and language development described in Genesis are correct in Guide for the Perplexed, Part III Chapter L and Rabbi Yehuda Halevi who says that evidence of pre-Adamic human civilization would weaken his belief in Kitab al Khazari, Part One paragraphs 60-61.

Among the suggestions I’ve seen to address this are that perhaps the scientists are severely mistaken, perhaps miraculous events would include aspects that obfuscate evidence of their occurrence, or that some opinions such as Rav Saadia Gaon do indeed allow for non-literal interpretations of these narratives (although only as a last resort, again as discussed in the Machzikei HaDas essay), either in total (e.g. "It teaches a deeper lesson") or in part (e.g. "Adam was the first man in a spiritual sense" or "Noah's flood was regional").

The Torah and Tanach appear to have contradictions

Another challenge is that the Torah and Prophets (though not necessarily the Writings) are supposed to be inerrant, yet some stories and verses appear to contradict with one another. For example, Numbers 33 and Deuteronomy 10 report conflicting versions of the journey through the wilderness and Aaron's death. In I Samuel 15 all of Amalek is killed, but by I Samuel 30 they’re pillaging Jewish towns. According to the genealogy in Genesis 46 Benjamin had 10 sons, according to Numbers 26 he only had 5, and there are differences about this as well in I Chronicles 7 and 8. II Kings 25 and Jeremiah 52 have various differences, such as whether Evil-merodach elevated and freed King Jehoiachin on the 27th of the month or on the 25th of the month. There are more examples, especially contrasting Chronicles (though being in Writings it may not have to be inerrant) with the narratives in the Prophets. So if the verses contradict, the Tanach must not be a reliable text, and it must not be that it was truly divine and inerrant.

Of course, Talmudic sages and later commentaries do offer resolutions to these contradictions, for example by saying that in one of the verses it meant something different from how it appears. Aaron's burial location in Deuteronomy was figurative as a rebuke to the Jews. Perhaps some of Benjamin's families had been totally wiped out before the Numbers census and genealogy. And so on. Since there are ways to say that these verses don't actually contradict, they therefore may not be a product of human authorship and error. Rather, such apparent contradictions may be intentional, explained in the Oral Law, possibly to convey deeper meanings.

The Torah may include anachronisms

This challenge is basically to say that the Torah makes certain references to places or things or events that shouldn't be in there and that would make more sense if it had been compiled over the roughly 900-400 BCE time frame that Bible critics propose. For example, in Genesis 11:28 and other places, Abraham is said to be from Ur Kasdim, which means Ur of the Chaldeans, yet it was not called the land of the Chaldeans until the 9th century BCE, and they could not have been around at all until at least the 11th century BCE. Or in Exodus 1:11 the Jews are credited with building Pithom and Ramses. Yet these cities were built later, for example Ramses was built for Ramses II who didn't reign till 1279 BCE, well after the Jews had left Egypt (which was 1313 BCE according to Seder Olam or even earlier factoring in the missing years).

There are various other examples in the Torah and Prophets. But again there are responses. Maybe the archeologists are mistaken, or maybe references in the Torah should be understood differently from how one might initially think. For example, maybe the reference to Ramses in the Torah was to a place not known to archeologists, and Egyptian rulers happened to have that name and a similarly named city afterwards. So while these details may be challenges to address, they don't necessarily make an earlier, legitimate authorship of the Torah untenable.

The Talmud makes erroneous statements

Another challenge to Judaism is to say that the sages in the Talmud made mistakes, and at least by some views, it is necessary to say that the sages couldn't have made mistakes, and even if they could, it doesn't speak well for their reliability in general. From the issue of the missing years where the Talmud considers the Second Temple period to have been significantly shorter than what is known from archeology of the time, to some views expressing a flat-earth cosmology, to apparently indicating that lice spontaneously generate, errors show the sages to be flawed. But these errors can also be explained within Judaism. Rabbi Natan Slifkin is noted for his addressing of discrepancies between chazal and science. By some opinions, you are required to believe that the sages did not make mistakes, in which case you may consider Talmudic errors to simply be allusions to their actual, deeper meanings. By other opinions, the sages are not considered infallible, and the only science that it matters for them to get right is when it relates to Halacha.

These are some of the big ones, but I have seen people presenting additional challenges, arguing that prophesies in the Tanach haven't come true, that textual oddities suggest human authorship, that stories and practices in the Torah are derivative of other ancient religions, and so on. Discussing and answering them all would be outside the scope of this answer. In general, the degree to which these and any other challenges to Judaism seem significant, and the degree to which their resolutions are satisfactory, will come down to a matter of opinion. It is an individual's responsibility to look into the facts and make a judgment of how innocuous or problematic such challenges may be and what degree of evidence in favor of Judaism is needed to outweigh them.

Arguments for Judaism

There are a wide array of arguments in favor of Judaism. Kiruv resources have gathered a variety of pieces of evidence and logical proofs. Some of the arguments are better and more common than others, while still more are unfortunately based on misinformation and don't serve Judaism well.

Misguided Proofs

I just think it's worth touching on this: A lot of proofs claim to show an amazing piece of knowledge contained in the Torah or Talmud or describe an amazing paranormal event but aren't really backed up by the facts. Unfortunately, they often get passed around without scrutiny, and that is counterproductive. I'm not saying that all amazing claims are necessarily false. But before something like that is repeated, it should be fact checked first to rule out misinformation.

Personal Experience and Miracle Stories

A fairly common argument that individuals use as evidence in favor of Judaism is stories of miracles or Hasgacha Pratis (divine providence). This is basically the category of supernatural coincidences. Often times they are a personal and anecdotal way of demonstrating evidence of Judaism to one's self or close peers. On the other hand, due to the nature of these stories, examples that impress oneself or a person's peers may not convince society as a whole. Some examples of stories I've heard involve prophetic dreams, precognition, miraculous healing, divine providence, and so on, and they go to attribute these events to God and take as evidence for Judaism.

The limitations of this line of evidence, though, are (1) that without having a personal experience yourself, you may not trust the supernatural event truly happened in the way the storyteller suggests, (2) that similar miracle stories are also commonly used by Christians, Hindus, and people of other religions, so unless Jewish stories can be meaningfully and qualitatively distinguished from other ones, it either is evidence of God but not a particular religion or it may not be a reliable way of determining the truth of something, and (3) these things may often be explainable by statistical expectations and cognitive shortfalls.

Bible Codes

Another line of arguments I've seen are on Bible Codes. Basically, when taking all the letters (without spaces) in the Torah (and Tanach too), starting with one letter and skipping a fixed (and ideally small) number of letters can produce new words, or skip codes. The idea is that there are groups of skip codes in sometimes relevant passages for related ideas that describe people or events. The idea is that these hidden codes show that the exact text of the Torah and Tanach were guided by an omniscient force. Although skip codes have no reliable predictive applications, proponents argue that there are statistically significant skip codes describing people or events which is enough to suggest divine authorship, which in turn implies that Judaism is true.

Not everyone is convinced by this, disputing the statistical significance, saying that skip codes can be found in any sufficiently large set of letters and that a skip code for anything can be found in the Torah (just as with other large works), including events that did not happen, and lastly that our modern Torahs may not have the original spellings which would in many cases erase the traces of intentional skip codes if there ever were any. It may indeed be that there are statistically significant hidden codes in Tanach demonstrating divine authorship, but it's hard to verify if that's really the case.

Archeology

Archeological evidence is another point that people use as evidence that the Torah narrative is true. Permission to Receive by Lawrence Kelemen has a chapter called the Empirical Issue which basically is a collection of archeological finds of ancient places or names or events that seem to corroborate the Torah's narratives. For example, an Ancient Egyptian story called The Tale of Two Brothers has similarities to the narrative in the Torah of Joseph and Potiphar's wife, and the Ipuwer Papyrus from Ancient Egypt seems to describe some of the 10 plagues of the Exodus from Egypt.

Such archeological claims are often disputed, however. For example, most scholars date the Ipuwer Papyrus to several centuries before the Exodus from Egypt would have been, and it seems to describe events that don't really match the 10 plagues. Using archeology can also be a double-edged sword, as mainstream archeologists tend to consider findings in Ancient Israel to be largely contrary to the slavery, exodus, conquest, and sometimes even the unified kingdom narratives. Without personal expertise, it may be hard for an individual to judge which archeological perspectives are more accurate, so this may also not be the easiest avenue to argue for Judaism.

National Tradition (aka the Kuzari Argument)

The "Kuzari Argument" may be the most popular argument in favor of Judaism. It is also a cornerstone of the Permission to Receive book described above. Succinctly, the Torah describes miraculous events experienced by the whole Jewish nation, and each generation learned about this from the previous. No generation would have accepted the Torah if it had just been made up by someone, especially since it contains a lot of doctrines and rules, because they could check with their elders to verify whether the stories were true. Therefore the Exodus narrative, and by extension the Torah received in it, are true.

Even this though is not a perfect proof. It depends on some assumptions, that the ancient Israelites were sufficiently incredulous, that at no point did a ruler force beliefs onto the people, that mythologies can't evolve much, that any religion the people might have had prior to the Torah would have been easier, and that at no point could a false, allegedly forgotten, history be "reintroduced" to the people. These assumptions are open to contention, and some of these assumptions may even conflict with narratives within the Tanach itself.

For example, it may be such mythologies really could develop naturally. Some argue that other cultures such as the Aztec and Sioux have national miracle myths. The narrative in Tanach may also not necessarily involve a continuous national tradition, as there are various places that state that at times God was forgotten and monotheism was rejected, for example:

And also all that generation were gathered unto their fathers; and there arose another generation after them, that knew not the LORD, nor yet the work which He had wrought for Israel. (Judges 2:10)

Further, perhaps a ruler could have indeed instituted religious reforms involving revisionist history, by authoritarian force and/or by claiming the history was forgotten. For example, King Asa is described as implementing with force religious reforms to spread monotheism and Torah to the people:

And they entered into the covenant to seek the LORD, the God of their fathers, with all their heart and with all their soul; and that whosoever would not seek the LORD, the God of Israel, should be put to death, whether small or great, whether man or woman. (II Chronicles 15:12-13)

Perhaps more relevant would be II Kings chs. 21-23, where a long period of time is described where the Jewish people were alienated from the Torah and practiced polytheism until it was discovered again by King Josiah’s scribe and High Priest. As a result, Josiah instituted religious reforms and restored monotheism, known as the Deuteronomic Reform, which may have been an opportunity for the king to introduce the people to a revised history of a national revelation under the pretense that it had been forgotten under the previous generations. Later the Tanach indicates that his reforms did not fully take hold until generations later when Ezra's followers finally seemed to have monotheism locked in. However, even his followers were largely ignorant of the contents of the Torah, as described in Ezra and Nehemiah, and some argue that this may have been another possible opportunity for new or altered narratives to be added to scriptures before canonization.

Despite such challenges, defenders maintain that the national miracle traditions really can't be faked and those Aztec and other counterexamples are not comparable. Some also argue that despite select verses which suggest a gap in tradition, other narrative details suggest that there must have always been at least some faithful tradition keepers. In the end, some consider the argument persuasive, while others do not.

Pascal's Wager

When it comes down to it, some people look at the evidence and are persuaded that Judaism is indeed true, others may have the complete opposite takeaway, and still more may have middling confidence. For this last group, an argument that they use to justify practice of Judaism is Pascal's Wager (which is an idea I heard expressed by Rabbi Dovid Gottlieb in conjunction with his version of the Kuzari argument). Their reasoning goes that they're not sure if the religion is true or false and that it's better to practice Judaism on the chance that it will help them in the afterlife. How good of a reason this is to practice Judaism may depend on how likely they think it is that Judaism actually is true, whether there are practical downsides to Judaism, what the consequences would be for a soul that doesn't practice Judaism, and (if the person thinks an alternate religion might also be true) what the consequences might be for following a false religion. So Pascal's Wager can often serve as a reason to follow Judaism. But it won't help anyone conclude whether Judaism is actually true.

There are, of course, various other reasons or pieces of evidence that are used to argue in favor of Judaism. Some argue for it on account of the survival of the Jewish people, the establishment and military successes of the State of Israel, numerology, the fact that the First and Second Temples were destroyed on the same calendar day, and so on. But again it is outside the scope of this answer to discuss them all, and it is up to the individual to explore and analyze their strengths and weaknesses.

Conclusion

Are these arguments sufficient to justify belief in Judaism? You will have to judge that for yourself. To that end, the statistical equation known as Bayes’ theorem can be especially useful in calculating the likelihood that Judaism is true by mathematically considering the various pieces of evidence. (See the addendum below for more information on using Bayes’ theorem.)

Based on the arguments I've seen, a case for Judaism can be made, yet it is by no means easy to definitively prove that Judaism is true. As far as why that should be, assuming of course Judaism is indeed true, other questions try to explore that as well as why God would require us to be religious when there are these doubts.

But as far as knowing "for sure" if Judaism is true, the fact is that there are arguments in favor of it but arguments against it. And what convinces one person might not convince another. It is up to every individual to examine the evidence and do their best to answer the question as honestly as they can.

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Using Bayes' theorem to calculate the probability of Judaism

Statistics can often be counterintuitive, so Bayes' theorem is helpful for factoring in pieces of evidence to estimate the probability that something is true. Specifically, it works by multiplying the prior odds that a hypothesis is true by the probability of there being a given observation if the hypothesis were true, divided by the total probability of there being that observation. There are various online resources explaining it more, but one helpful video is A Visual Guide to Bayesian Thinking by the rationality public speaker Julia Galef.

A caveat here is that for topics such as this, it relies largely on an individual's best assumptions rather than clearly known probabilities. And due to differences in the knowledge different people have about various issues, or personal biases that skew what they consider reasonable, what one person considers to be a reasonable probability to input may differ from that of another. Consequently, although this can be useful, it will still not produce a single, definitive value for all people. Individuals must also be mindful of potential biases (e.g. if they think an expected probability for a piece of evidence is extremely dependent on Judaism being true, they should ensure they know enough about the issue to honestly justify that confidence). Of course, this is still far more reliable and useful than a simple gut feeling, which is all anyone can reasonably ask for.

The equation can be written like:

P(J|E) = P(E|J) x P(J) / [P(E|J) x P(J) + P(E|~J) x P(~J)]

Where P(J|E) is the posterior probability that Judaism is true, P(E|J) is the probability of specific evidence existing assuming Judaism is true, P(J) is the prior probability that Judaism is true before considering that evidence, P(E|~J) is the probability of the evidence existing assuming Judaism is not true, and P(~J) is the probability that Judaism is not true (which equals 1 - P(J)). The value for a probability can range from 0 to 1 (e.g. 1 = 100%, 0.05 = 5%, etc.).

The equation in this form only factors in a single argument (or piece of evidence, or observation), so to get a final estimate, you would need to take the result of the equation, treat that as the new prior probability, and repeat the calculation for the next argument. (The order for calculating the various arguments does not matter for conditionally independent observations like this.) You don't have to factor in every argument there is, just the significant ones, both for and against, where whether Judaism is true or false would make a significant difference in your expectation of those arguments existing.

Example using Bayes' theorem

I'll give an example of using the equation, but I cannot run the actual calculations on behalf of others as the numbers I would offer would be based on my personal knowledge and estimates and colored by my personal biases. So for illustrative purposes only I will give an example using values that I do not necessarily endorse:

So first, we need to come up with an initial P(J). That is, if you didn't have any evidence for or against Judaism, what are the odds that it is the one true religion? There are thousands of religions today, about twenty that have millions of followers. A person might consider all religions to be equally plausible, or a person might know certain things about some of those religions to discount them. Some may think it doubtful that there even is a true religion. Just for our example let's say a person thinks there is a 50% chance that there is a true religion among the largest 20 religions, and they do not initially necessarily consider any one of those religions to be more likely than any other, so we'll set the prior probability that Judaism is true as 0.5 * 1 / 20, or P(J) = 0.025 and P(~J) = 0.975.

For an argument to factor in, let's do the establishment of the predominantly Jewish state and government of Israel. Let's say that you would have only expected a 5% chance that the Jewish people could have succeeded in establishing a state naturally, whereas if Judaism were true you would expect maybe a 50% chance of God enabling the establishment of a state in this way. So we say P(E|J) = 0.5 and P(E|~J) = 0.05 leading us to:

P(J|E) = 0.5 * 0.025 / [0.5 * 0.025 + 0.05 * 0.975)]
P(J|E) = 0.204

Considering a first piece of evidence in this way raised our probability that Judaism is true from 2.5% to 20.4%, which is a significant change. Next let's say we want to factor in the effect of the Kuzari argument. Let's say we find the argument fairly compelling, expected if Judaism were true and fairly unlikely that it would have come about otherwise, and we may judge that P(E|J) = 0.9 and P(E|~J) = 0.1. And now we can also set a new prior probability from our posterior probability result of the last equation, so P(J) = 0.204 and P(~J) = 0.796. Which means:

P(J|E) = 0.9 * 0.204 / [0.9 * 0.204 + 0.1 * 0.796]
P(J|E) = 0.698

We now have gone up to a probability that Judaism is true of 69.8%. To wrap up our example we'll factor in a counterargument, apparent anachronisms in the Torah. Let's say that a later authorship may lead to some anachronisms, but also that it's plausible that those references in the Torah have been misunderstood or the archeologists would make mistakes. We might decide P(E|J) = 0.5 and P(E|~J) = 0.75. And from the previous calculation,P(J) = 0.698 and P(~J) = 0.302. So:

P(J|E) = 0.5 * 0.698 / [0.5 * 0.698 + 0.75 * 0.302]
P(J|E) = 0.606

With this, the posterior probability that Judaism is true has decreased slightly to 60.6%. And to continue refining our value of the probability that Judaism was true, we would continue doing this math until all the significant evidence is considered and we have a useful final calculation that represents how likely we believe it is that Judaism is true.

This should only be considered as an illustrative demonstration of how to utilize Bayes' theorem to figure out how likely you believe it is that Judaism is true. But do the math as modeled above, using values that you yourself consider reasonable, and it will help you reach a useful number to tell you how likely it is Judaism is true.

Answer 2

Rabbi Kelemen’s book Permission to Receive is essential reading and provides four rational approaches to the Torah’s Divine origin. I can’t summarise it here.

The best evidence is our Mesorah – the tradition of transmission of the Torah.

The link site also has articles on our history with the critical paragraph:

On the fiftieth day after they began counting the Omer--that is, fifty-one days after the Exodus, all of the Children of Israel, men, women and children, over two million people, stood at Mount Sinai and received the Torah amidst great miracles and heavenly fire. They saw no form or picture of G-d, but they saw many miracles that proved that G-d is the Creator of heaven and earth. They heard G-d's voice speak and command Moses to instruct the Children of Israel on how to prepare to receive the Torah. Then they heard G-d speaking directly to them, the Children of Israel, and commanding them to keep the Torah. The Children of Israel accepted the Torah and all its Commandments, and they said: "We agree to obey, even before we hear the actual Commandments."

The article that establishes the age of the Torah is also worth looking at.

We have had the Torah for at least 3,313 years, when Hashem gave it to us at Mount Sinai.

Answer 3

there is no water-tight proof for Judaism (or God) since we believe the purpose of creation is free will (see Derech Hashem ch.1). But there are many indications of its truth, which although each one by itself may not be so convincing but the sheer number of these indications is enough to be considered sufficient proof.

The first thing a person needs to do is investigate whether God exists and is involved in our planet. This can be derived through philosophical inquiry (first cause) and through the wisdom in nature, especially in life forms on our planet. Once a person is convinced of the existence of God and that He is involved on our planet, and is concealing Himself from us, then it follows that some communication should occur for Him to tell us what this is all about and thus one religion should be true. Based on below and more, I believe Judaism has vastly more tangible evidence without comparison than any other religion out there.

1. the laws of shmita (Parsha Behar) (every seven years everyone in israel must stop working the land for the whole year. God promises to provide a bumper crop prior to the Shmita year to sustain the Jewish people). furthermore, in the yovel year this would be two consecutive years where noone planted anything. What human in his right mind would fabricate such a claim and risk mass starvation? (if this were agricultural reasons, it would not be necessary to stop all the land simultaneously and it would be crazy to promise a bumper crop after six straight years of harvesting the land. Usually the opposite happens after 6 straight years.)

2. 3 times a year, every year, during the temple era, all Jewish males are commanded to leave their homes and go to Jerusalem for the festivals. God promised: "Nobody will desire your land while you are going up to see the face of the Lord your God three times in the year." (Ex 34:24) Who else could make such a claim but God? No human being in his right mind would enact such a law, leaving his army vulnerable to being encircled and easily defeated. Turns out it proved true that no foreign nation ever came up to take the land of the Jews during their festivals prior to the destruction of Jerusalem 400+ years later.

3. Kosher. The torah informs us that there is only one animal that has split hooves and does not chew its cud - the pig. Who else but God could claim this? (see this link for more on this: http://www.aish.com/jl/b/bb/104491254.html )

4. "all fish with scales have moving fins" - who else but God can claim this. (see above link). (some invoke the "sea snake" or "sea eel" as a "refutation" but these scales are embedded in the skin unlike normal fish which are armor-like and come off without peeling off the skin. the hebrew word for scales "kaskasim" is the same as for armor. see: this or this)

5. The torah's prophecies of the return of the Jews to Israel. (can a nation exiled from its homeland and splintered into a dozen minor ethnic groups for 2,000 years, have the ability and resolve to return en masse to their homeland and become a universally recognized world power?)

6. Miraculous victories of the israeli army in the early wars (see for example: http://www.chabad.org/multimedia/timeline_cdo/aid/525341/jewish/Introduction.htm or http://www.benmelech.org/z-def/english/israel-bailey.htm) Even Ben Gurion who was a secular Jew is quoted as saying: "In Israel, in order to be a realist you must believe in miracles".

7. The Tzadikim - those who have had the merit and opportunity of meeting with the Tzadikim (righteous sages) of the generation know that even today, we can find shadows of "prophecy" (see the books Shaarei Kedusha or Mesilat Yesharim for how these great men got there and that this path is open to everyone)

8. the infinite wisdom/depth of the Torah, which is evident to all who study it in depth.

9. The uniqueness of the hebrew language. There is something much more to it than plain convention as explained here. see also DNA of creation by Rabbi Becher here or the book "Letters of Fire" by Rabbi Matityahu Glazerson

10. Jews don't go around trying to convert nonjews. on the contrary, they try to discourage potential converts, that it will be too much for them to take on. This is due to confidence in the pact of God with Abraham that Judaism will never disappear as explained here. We see its effects today, as Mark Twain wondered: "The Jew saw them all, survived them all, and is now what he always was, exhibiting no decadence, no infirmaties, of age, no weakening of his parts, no slowing of his energies, no dulling of his alert but aggressive mind. All things are mortal but the Jews; all other forces pass, but he remains. What is the secret of his immortality?"

11. The uniqueness of the Jewish people, in terms of cultural survival as explained in this lecture by Rabbi Mordechai Becher. This indicates a special providence on the Jews more than any other nations as explained there. We also find a uniqueness around the jewish people in terms of intellectual abilities. They have received an extremely disproportionate number of nobel prizes. This indicates "something" unique about the Jews.

12. Antisemitism - The Talmud (Tractate Shabbos 69) cites the source of anti-Semitism using a play on words: The Torah - the source of the Jewish system of laws, values and moral standards - was received at Mount Sinai. The Hebrew pronunciation of "Sinai" is almost identical to the Hebrew word for "hatred" - sinah. "Why was the Torah given on a mountain called Sinai?" asks the Talmud. "Because the great sinah - the tremendous hatred aimed at the Jew - emanates from Sinai." I think we can confirm the existence of this irrational hatred throughout history. Even today, the UN passes more resolutions against Israel than the entire world combined. Some Jews have tried to cure this hatred by abandoning the torah and becoming like the nations but history shows it has resulted in the opposite effect, as predicted in the verse (Ezekiel 20) "When you say, 'Let us be like the nations, like the peoples of other countries...' As I live says the Lord GOD - I will rule over you with a strong hand, an outstretched arm, and outpoured wrath".

13. The special providence given to those who truly dedicate themselves to torah study. The Vilna Gaon for example reportedly achieved superhuman levels of torah wisdom as explained here and here. More recently, it is reported in the book "HaSod" by (Y. Hershkowitz) about Rabbi Yosef Shalom Elyashiv that his grasp of the entire spectrum of torah depth was miraculous. He was able to answer the most complicated halachic questions instantly, even those intertwined in multiple complex sections in the talmud over many tractates. Many times the head judge of the Rabbinical Court in Jerusalem was asked to rule on such complicated questions. He would answer: I can research this and give you an answer in several days, or you can go to Rabbi Elyashiv and get a fully reliable answer instantly.

14. The uniquenes of the torah. the most popular book of all time. Even today it has been translated into more languages than any other book. The two great world religions - Christianity and Islam are daughters, though sometimes ungrateful daughters, of Mother Zion. Whether or not they realize it, they have spread to humanity, at their level, major concepts of Judaism.

15. Judaism is the mother of all monotheist religions. Scientific inquiry supports the idea that the world functions through a unifying force as explained in this lecture by Rabbi Mordechai Becher. This is an indication that if the universe is run by the divine then there is only one Divinity.

16. Despite being among the smallest nation, the Jews are the most influential people in world history. Among many others, John Adams, a non-Jew and the second president of the United States said: "I will insist the Hebrews have [contributed] more to civilize men than any other nation. If I was an atheist and believed in blind eternal fate, I should still believe that fate had ordained the Jews to be the most essential instrument for civilizing the nations ... They are the most glorious nation that ever inhabited this Earth. The Romans and their empire were but a bubble in comparison to the Jews. They have given religion to three-quarters of the globe and have influenced the affairs of mankind more and more happily than any other nation, ancient or modern". End quote. A nice short movie on the Jews was made on this

17. End of Days - we have a tradition that the Jewish calendar will not exceed 6000 years (Rosh Hashana 31a, Sanhedrin 97a, Zohar 1:117a) (current year:5777). We can see in our times the pace of events accelerating exponentially more than any other time in world history.

Two more points brought by Rabbi Yaakov Emden (200 years ago, quoted in Masoret Yisrael edition of Chovos Halevavos end of gate 10):

The sign of the truth of these things are from two faithful, visible, witnesses:

One, our situation and survival in this long exile, which the Creator fulfilled His promise: "But despite all this, while they are in the land of their enemies, I will not despise them nor will I reject them to annihilate them, thereby breaking My covenant that is with them, for I am the L-ord their G-d" (Vayikra 26:44)...

Two, the matter of our land, because from the day we went out of it, no nation was able to dwell in it, it was like a woman who's husband went on a faraway trip, and she waits for him, and the verse "I will make the Land desolate, so that it will become desolate [also] of your enemies who live in it" (Vayikra 26:32), tells us it is guarded for us...all this are clear signs that our hope is not lost and G-d's love has not left us, and on this eternal love is based Shir Hashirim, and just like G-d loves us a strong love, "Torrents of water are not able to extinguish the love" (Shir Hashirim 8:7), so too it is our duty to show our powerful and complete love, like "As water reflects a face back to a face, so one's heart is reflected back to him by another" Mishlei 27:19)

Rabbi Matityahu Solomon, the mashgiach of the Lakewood Yeshiva in New Jersey also brings down a different version of Rabbi Emden's argument in his commentary to the Shaar Bechina ch.5:

We do not need to contemplate on the great miracles of the Exodus, in order to examine and demonstrate G-d's goodness and infinite power. For behold, we have a faithful witness which cannot be denied - our survival during this exile among the nations. It is proper to quote the holy words of Rabbi Yaakov Emden (sidur beit kel):

"Who is so blind as to not see the divine providence below, that His eyes are on them always. How could the denier of providence not be ashamed and stand disgraced? He who examines our unique situation and standing in the world. We the exiled nation, a dispersed sheep. After all the troubles and shifts for two thousands years. No nation in the world is as pursued as us. How great have been our troubles! How powerful have been those who lifted their heads against us from our earliest beginnings - to exterminate us, root us out, and eradicate us, due to their intense hatred which stems from jealousy. They have brought on us great sufferings but were never able to triumph over us, to eliminate us and destroy us. All these ancient, powerful nations - have gone by, their strength has withered, their protection has eroded - but we who cling to G-d are all alive today (Deut. 4:4). We have not lost in this long, intense exile even a single letter or vowel of the written Torah. The words of the Sages (oral law) endured. The hand of time did not prevail over us, they were not able to prevail over us. What will the sharp philosopher answer to this? Can the hand of chance do all this? I swear by my soul, for when contemplating these things, they are greater in my eyes than all the great open miracles G-d has performed for our forefathers in Egypt, the Sinai Desert, and in the land of Israel. (the author wrote that the miracle of our survival in this exile is equal to the miracles of Egypt, but Rabbi Yaakov Emden holds that it is an even greater miracle) The longer the exile, the more the miracle is confirmed, and G-d's strength and power becomes apparent. For the prophets already saw the exile's intensity, complaining and moaning on its amazing protracted length before it happened. Behold, none of their words fell to the ground (failed to happen)..." End quote

(Rabbi Solomon continues) As Moshe Rabeinu told us from the outset that such and such as trouble would befall us, and thus it happened. Likewise, for all of our exile - the prophets already predicted what will happen. For all the persecutions and pursuits that befell us, such as the holocaust, it is all spelled out in the verses of the Torah which speak on those times... Can we not see these things with our own eyes?! Behold, only by examining and contemplating is it possible to see them. Without contemplating them, we remain totally blind.

and all this is just the tip of the iceberg. for many more indications I put together see here

Answer 4

We can't. But we can, by learning about Judaism beyond its superficial characteristics, see glimpses of its many lowercase-truths: its reflexive truth, its genetic truth, its referential truth, its subjective truth. And these put together come as close to "Truth" itself as humans are liable to arrive in this lifetime.

Is beauty true? Keats's doomed Grecians certainly thought so; perhaps, then, it is no coincidence that a kosher Torah scroll may be written in ancient Greek. For the Torah is beautiful; its many, many parts fit together perfectly, even where they seem not to do so at first or at second or even fiftieth glance. Is this evidence of a Divine origin? Maybe. Is it evidence that the Torah is internally true--that is, that it is completely integral, harmonious, coherent, and pure, like the notes of a correctly-tempered scale, or Da Vinci's ratios? Yes--and arguably it is better and truer than any of these, for its beauty is composed of far more dimensions of depth and historicity, on a far grander scale, and with a sweep which reaches farther, from the first flickers of light until the last breaths of humanity. As such, it had the gravity to inspire both Bach's partitas and Da Vinci's paintings.

The genetic and referential truths of Torah are, in my opinion, the simplest elements of its Truth. These have to do, respectively, with Torah's historicity and its power to correctly predict and reflect the world.

Torah's power to correctly predict and reflect the world has been discussed interestingly in other answers. There are numerous, very striking examples of Torah's uncanny and precocious accuracy in describing phenomena of nature, biology, chemistry, astronomy, and even the physics of the last century--to say nothing of its brilliant and subtle philosophical assertions, whose truth becomes powerfully clear through lived experience. All these "discoveries" carry with them a certain magic, magic having both edges of spiritual inspiration and susceptibility to bias: the more one learns, the more truth and internal and external resonances one finds in the Torah. One runs into some truths that are merely felicitous and delightful; some that are astounding; and some that are profoundly moving. Arguably, though, these work upon the heart and soul so engagingly that the mind has trouble keeping pace, forgetting, at times, to present the ticker of things encountered that are less true, or that are patently false, or that are only true because of tricks and sophistications.

But when one chooses to live by the whole Torah, the total of these truths points quite compellingly in a certain direction. Here, the combined evidence is greater than the sum of its parts; perhaps exactly this is what constitutes the individual experience of Truth. That direction is the good and proud and kind life that comes from Torah. It points to individual survival--to happiness, spiritual peace, health, community, stability, relationships, and pride--and, 'בעזרת ה, to survival through children, survival across generations, and survival as a people through havoc and adversity, moreover with great success, with money, with flourishing statehood, and with prodigious achievements and contributions in both humanity and intellect, B"H. This is the most basic evidence of one facet of Torah's truth, its referential truth as it applies to life--Torah describes correctly, and it prescribes correctly, and by its prescription, our people have lived on and on and thrived against unfathomable odds.

Moving on to the Torah's authentic origins, its historical truth: The written and archaeological records supply, indeed, ample evidence of a naturally-enabled escape by the Jewish slaves from Egypt, followed by some unusual geological or meteorological event at Sinai. The idea that the basic events of this account were made up, that 600,000 people were initially convinced of the lies, and that the lies survived in their original form for 65 generations thereafter (because the fervency of this belief caused parents to impress it on their children at every cost) is difficult to conceive. Still, it is not impossible, given that other religions have achieved nearly the same with their incompatible accounts. But even this we must question: 1) Are their accounts really incompatible with ours? --Up to a certain point, no. And after this "certain point," the Jewish chronicle of faith essentially ends, whereas others diverge and go further. 2) Did other religions really achieve the same? No, because their tenure is much shorter. Only Judaism and perhaps some early forms of Hinduism (on which my lack of knowledge prevents me from commenting) have existed for anything like the length of human history. So the tenure of Jewish belief really is quite remarkable, and lends some credence to its authenticity. Humans have simply never believed anything for as long, and with such consistency.

How we jump from "is" to "ought"--from historical facts to the Law, and its current force on us--is, as always, harder. I admit a gap where it comes to the question of whether G-d spoke to Moshe Rabbeinu and said such words, or whether the Jewish people, astonished at the miracle of their liberation, and at the formidable evidence of G-d they saw at the mountain, took upon themselves a code of law as a testament to their love and fear of this G-d. After years of pondering this question, I eventually moved from a quite firm conviction of the latter to a far firmer conviction of the former, mostly as a result of newfound humility through learning. In any case, the upshot is the same--and arguably, subtly, the cause is the same, too. If one believes that a single G-d moves the world, including its humans, then one believes that the Law began as a reciprocal covenant between humans and G-d.

Though it seems most difficult at first blush, it is in fact very easy to see and believe that the mesorah--the interpretation of Jewish law developed across rabbinical history until today--is true to the original sense of the Law. One comes to this belief by learning about the tradition of transmission and interpretation itself. The amount of rigor, devotion, and intelligence that went into this work--and still go into it--is staggering. The number of whole lives of whole men, to say nothing of man-hours, dedicated exclusively to this effort boggles the mind. The idea that one, in a few hours or a few lifetimes of skepticism, could outthink these geniuses, could outdo their combined work, is folly and idiocy (--not unlike, I might add, the folly and idiocy of some half-baked religious criticisms of the mesorah of science). The only defense of that armchair endeavor is that the human soul retains its sovereignty, and the human spirit its power of self-determination, in spite of any weight of evidence or practical calculation. And with that I turn to subjective truth.

Maybe the Torah is not True. What, after all, is Truth? We have learned from The Matrix and Descartes that existence itself may be a sham. Perhaps we are only dreaming, or are in someone else's dream. And even if, big if, we really exist, we are only humans, who might as well be ants in our ability to assess life and to "understand G-d." What gives? How could we possibly decide from this fragile standpoint that the books in our library represent the sum total of G-d's Truth?

We can't. And this fact is not lost on Jews. But, all the same, we know that Torah is true to us. If we are ants, then the limit of our brains is the space between the thorax and the mandibles. And yet we live in this space. This space is also the limit of our existence. Just as we will never be able to see or travel farther than the speed of light can do in one lifetime, we will never be able to think, or conceive, or read, or believe farther than this space will let us.

And so we make do, in the meantime finding what appeals to our little brain's finest senses of justice, reason, rightness, and meaning. We see what has been true for the best humans, from Moshe Rabbeinu down to our beloved grandparents. We see if it seems to be true for us. And now and then we do our limited best to turn and face G-d ourselves, and see if we can discern an answer about how best to serve Him. We have no choice: the day is short. The task will not be completed; but, our Fathers tell us, we must begin somehow.

Torah's dignified, subtle, and intricate philosophy of personal and communal obligation, duty, and justice, as well as its stringent insistence on G-d's singleness, are the working through in human dimensions of extremely basic, and yet extremely innovative principles. These are easily taken for granted by those who have Western civilization as their birthright, but they were really at one time revolutionary, and would be so again if we lost them, ch"v. And thus, although neither the reflexive truth, the genetic truth, the referential truth, nor the subjective truth of Torah is alone dispositive, taken together, they form an image that, if not enough to kill for, is enough on which to base life and lives.

*It's not our job as humans to figure out what is true, because we can't. It's our job to figure out the best way to live.

B"H

Answer 5

From the very fact that there are so many heated disagreements between Jewish groups, and even within each group there are disagreements, yet they all concur on the essential beliefs in Judaism it must be true.

For example, (besides believing in תורה מסיני and in Moshe Rabeinu and things like that) there is no group within Jews who use less than 10 men for a Minyan; There is no group that does not make Kiddush on Shabbos (except if it's Yom Kippur); A big one is, the fact that even though the Torah says about the month of Nissan החודש הזה לכם ראש חדשים and there is a disagreement (between R. Eliezer and R. Yehoshua) if the world was created in Nissan or in Tishrei, yet you will not find a Jew who will tell you that Rosh Hashannah is the first day of Nissan!

Answer 6

from an experiential point of view, in my opinion, the greatest proof of Judaism is from the Tzadikim (great torah scholars of the generation).

in several places, meeting the Tzadikim is compared to greeting the divine presence. One can feel holiness around these people and be filled with a sense of humility. This is so even today despite the drop in generations.

as for those of previous generations who were on far higher levels, we still have many of their original works and can tangibly see their superhuman levels of wisdom and holiness. see the books of the Maharal for example.

some sources:

Maimonides - Igeret Teyman (translation from here):

"There is no comparison between our religion and the other religions who wish to copy us. It is like the difference between a living, aware, human being versus a statue cut out of wood or moulded from metal, i.e. from silver or gold, or chiselled from a block of stone or marble until it was in the form of a man.

The fool who does not recognize divine wisdom and does not know sculpturer skill sees the statue in its superficial appearance of man and thinks it is the same as a man. For he does not know the interior of both. But the wise man, who knows the interior of each one knows that the interior of the statue has no wisdom while the interior of man has wondrous true wisdom and engineering which reflects divine wisdom. When he studies the muscles, tendons which cause his movements, and the various organs, etc. and his joints, etc. etc. everything in its proper place and function...

So too, is the difference between the fool who does not know the inner meaning of the holy writings and the commandments. When he wants to compare our religion with that of other fake religions thinks there is some similarity between them. For he sees in both of them things permitted and forbidden, procedures and ceremonies, etc. But if he knew the interior of the divine religion (Judaism), that it contains things which lead to perfection of man and protection from the opposite, and to virtuous traits and perfect wisdoms, for the masses according to their ability and the special individuals according to theirs... while those religions who would pretend to be like ours have no internal content, only stories and imaginations invented by their founders for his own glory.. until the matter is a joke and a mockery just like people laugh when they see an ape dressed up to act like a human being..."

also Duties of the Heart gate 6 ch.5

When one contemplates the greatness of the Creator and His infinite might, who observes one's outer and inner life. When one fixes his mind on this great theme and considers what our sages report regarding the impressive and awesome presence of the pious sages in previous generations, for example "he (Rav Sheshes) gazed his eyes on him and the man (died and) became a pile of bones" (Berachos 58a), or as it was said of Yonatan ben Uziel: "when he would expound the torah, any bird that would fly over him was instantly burnt."

Talmud Moed Kattan 17

Rabbi Yochanan said: "What is the meaning of the verse: 'For the priest's lips should keep knowledge and they should seek the torah from his mouth; for he is an angel of the Lord of Hosts' (Malachi 2:7)? [It means, that] if the Teacher resembles an angel of the Lord of Hosts, they should seek the Torah from his mouth; but if not, they should not seek the Torah from his mouth

to summarize, one can know the truth of Judaism by looking at the results - namely the great tzadikim who attained supernatural levels of wisdom and holiness. Likewise by studying the works of those of previous generations with proper respect. This is an experience with the divine truth of Judaism which is far more powerful than abstract rational arguments which always have holes.

Related to this is torah study itself, where one can experience to some extent the divine presence in the torah as brought in Pirkei Avot:

Rabbi Chalafta ben (son of) Dosa of K’far Chananya said: When ten people sit and study Torah, the Divine Presence dwells among them, as the verse states, ‘The L-rd stands in the assembly of G-d’ (Psalms 82:1)...How do we know even one? As it states’In every place where My Name is mentioned I will come to you and bless you’ (Exodus 20:21).” see here for more.

Answer 7

Rabi Umori, Harav Yosef Mizrahi has a three part lecture called Torah and Science where he proves with irrefutable proofs that the Torah is Divine and that Islam and Christianity are nonsense. It is around four hours but it 100% worth it in my opinion for Hizuk and evidence.

Here are a few from Harav Mizrahi (and possibly other sources):

• The Talmud states (Berachoth 32b) the following “Said to her the Holy One, Blessed is He, my daughter, twelve Mazaloth I have created in the sky, and for Mazal I have created thirty Chil and for each of the Chil I have created thirty Legions, and for each Legion I have created thirty Rahaton and for each Rahaton I have created thirty Karaton and for each Karaton I have created Gastra and for each Gastra I have attached 365,000’s of 10,000 of starts, corresponding to the days of the solar year, and all of them I have created only for your sake.” The total number of starts in the universe is 1018 or 1,064,340,000,000,000,000,000. According to the Arizona State University, the number of stars in the world is about 10⑱. Interestingly enough, the Talmud was written over 1700 years ago, while the gentiles in the world presumed there were about 4000-8000 stars (see Raziel HaMalach pg. 54).
• According to Chochise College: “They theory of Pangea is that millions of years ago all the continents were joined together in one enormous land mass known as Pangea.” The super-commentary on the Bible, the Iben Ezra writes (Genesis 1:2) in accordance with this statement. He writes quote “First G-d created one continent, but then split into seven continents. The Iben Ezra lived from 1089-1164. Iben Ezra lived before Australia, Antarctica, and America were discovered. Until recent years this was not known to gentiles, however since our sages have divine assistance in all their works, they receive knowledge that is not known to the regular man. Thus revealing the knowledge that G-d has before all others.
• The prophet Jeremiah writes (Jeremiah 50:9) “For, behold, I will stir up and cause to come up against Babylon an assembly of great nations from the north country; and they shall set themselves in array against her, from thence she shall be taken; their arrows shall be as of a mighty man that make childless; none shall return in vain.” The essential commentary, the Malbim writes 200 years ago “The arrows strong as is smart; the enemy’s arrows will be like they have a ‘brain’ and they will take themselves to their destination.” Jeremiah, over 2500 years ago knew about the Gulf War, and the Malbim knew about the missiles that control their own path.
• Due to our advanced knowledge of science, today we have learned that when the snake sheds its’ skin it feels excruciating pain. We only received this knowledge merely 50 years ago. However, the Bible knew of this 3320 years ago. The verse reads (Genesis 2:14) “And the Lord God said to the serpent, ‘Because you have done this, cursed be you more than all the cattle and more than all the beasts of the field...’” Meaning the Torah knew of the pain that the snake was feeling much before modern science discovered it.
• The Talmud (Nidah 6:9) states “Everything in the ocean that has scales must have fins.” Keep in mind, this text was written over 1800 years ago. The text is almost saying that they have searched through the millions of species of animals in the ocean and never saw a fish that has scales and not fins. The only possible way that that Rabbi could have known this is 2000 years ago, is if they either went to the depths of the ocean (without submarines or special technology) and studied every living creature beneath the water (something that even scientists today haven’t even completed yet), or they had recieved it through tradition from Mt. Sinai.
• Scientists today have learned that water does exist in the cosmos. However, our Torah knew about this many thousands of years of years ago. The verse states (Genesis 1:7) “And created the firmament; and He separated between the waters beneath the firmament and between the waters that are above the firmament.”
• The Torah states (Deuteronomy 28:36) “And you shall serve other gods of wood and stone...” As mentioned many times the Torah is over 3300 years old in its revelation. Thus it shouldn’t have known about Christianity 1300 years prior to its beginning or about Islam 2000 years before it began. However, it did because as we know Christians worship the cross, and Muslims worship wood (Mecca), and Vilna Goan (Adereth Eliyahu) explains this verse in this way. Hence, the Torah knew about them many years before they even began.

And many, many more...

Answer 8

While all other religions have unanimous bind faith, Judaism has a unanimous verbal transmission. Plus there is no alternative Jewish history.

Answer 9

Important question, and very interesting answers. I'd like to try to contribute a comment based on a combination of R' Micha Berger's answer, and Aaliyah's answer (which quoted Bayes Theorem).
Let me give an example, "לשבר את האוזן". Three people have different opinions on whether a coin is fair, or always heads. They start flipping it, and it keeps coming up heads. The one who thought it was loaded has his judgment confirmed each time. The one who thought it was probably fair will continue to think so for a little while. Around the fifth flip he may say, Well, I thought it was unlikely to be loaded, but it's also unlikely to come up heads five times in a row. I should reconsider.
And the one who thought it was less than a chance in a thousand that it was loaded will say, This is kind of unlikely - but not nearly so unlikely as the coin being loaded!
But keep flipping it; at ten or surely twenty more times he will change his position too.
All this is clear and can be quantified with Bayes' Theorem. And none of them is being unreasonable, depending on what they knew when we started.

Okay, now for a bad analogy! Let's look at the groups of people in Egypt before the Exodus. Moshe and Aharon had a mother who knew Yaakov Avinu! Whoa. On the other end of the world, Pharaoh thought he was a god, "Hashem" was a name that didn't register with him at all. And in between were the elders of Israel, the rest of the nation, the Egyptians, the chartumim... with a lot of individual variation.
Now Moshe came back. After his first signs, Israel believed in him. [Some of them would change back when things got hard soon after.] After a couple of plagues, some of Egypt flipped. After a few more, the chartumim admitted that what was happening was beyond them. There were still the "ones who feared the word of G-d" (Exodus 9:20), and, those who still didn't. By the end of the plagues, Pharaoh was all alone. After the plague of the firstborn he flipped as well.
Understand - none of them were being unreasonable. It would be unreasonable to expect an Egyptian to react the same way as Moses. In Bayesian terminology, his "priors" are completely different.

Back to us. I think the standard Orthodox response to the fact that the rest of the world thinks that our "proofs" are irrelevant is to say, Of course they do! They don't want to accept reality. They don't want to deal with a G-d who will establish the way we should live our lives. They don't want to change.
I'm sure that's true. We all do that with unwelcome news - including Orthodox Jews!
But I think you can say a little more. Right now, those of us who are connected to our traditions have enough for us to accept the reality of the Torah. After Har Sinai, Hashem said about our nation, "they will believe in you[r prophecy] forever" (Exodus 19:9). We are right to do so, as the Kuzari says. We don't have open miracles these days, but Hashem gave us enough to keep us going.
That doesn't mean that a secular scientist has enough yet! Nothing is wrong with that, that's the way it was then, and will be the way it works now. Until enough things will happen that all the world will understand the truth of Hashem and his redemption, בב"א.

Answer 10

I believe there is at least one airtight logical proof of G-d's Existence out there, somewhere. However, I do not believe a person would be ever able to show that it indeed has no holes. And I believe that someone who is inclined to deny His Existence will find non-existent "holes" in that proof that no one could ever prove to anyone's satisfaction are indeed fictional.

In other words, the whole notion of proof really fails the question of "how can we be sure?" because humans are not capable of ever being sure a proof is valid.

This realization hit philosophy in the 15th cent CE or so. The kind of critical thought used by the later Scholasticists (Duns Scotus, William of Ockham and the like) undermined belief in the Scholastic project altogether. And then in comes the Renaissance and Humanism, the Idealists vs the Empiricists, then Immanuel Kant and Modern Philosophy. Kant's "Copernican Revolution" turned the whole idea of proof on its head.

Modern Philosophers would very much agree with Rav Yehudah haLevi's observation, “The Rabbi: That which you describe is religion based on speculation and system, the research of thought, but open to many doubts. Now ask the philosophers, and you will find that they do not agree on one action or one principle, since some doctrines can be established by arguments, which are only partially satisfactory, and still much less capable of being proved.” (Kuzari 1:13)

And now we live in an era in which Post-Modernism has reached general culture. There is a trend in many circles to consider only scientific truths to qualify of Truth, and anything else to be a matter of opinion -- "his truth" or "his narrative". In a world that refuses to draw distinctions between the Israeli and Palestinian narrative over "minor" issues like which one is historically accurate, we cannot hope people to be convinced of objective religious Truths through the old methodologies.

People today may be more convinced by Existential answers than abstract proofs. One of my signature files, the only one that’s a self-quote, reads, “The mind is a wonderful organ for justifying decisions the heart already reached.” After all, it is the fact that a given set of postulates yield results consistent with my experiences that gets me to judge them self-evident rather than some other givens. This echoes the King of the Kazars' objection, that for any philosophical position justified by argument, there are conflicting opinions whose adherents claim equally valid arguments.

The Kiruv Movement is not founded on philosophical dispute. The most effective kiruv tool is the experience of a Shabbos. People do not accept the proofs of G-d and the Divine origin of the Torah and halakhah and therefore keep Shabbos. Rather, they experience Shabbos, get first-hand experience of the power of halakhah, and based on that believe in the authenticity of the Torah and its own claims about its origin.

In addition to the experience of performing mitzvos, Torah study too has this defining characteristic. Torah has an elegance one finds in the most “beautiful” of mathematical proofs despite tackling concepts far less simply defined. A discussion of the laws of theft could explain a seemingly unrelated point in the laws of Shabbos with a single theory (sevarah) uniting both.

I should be clear that I’m not speaking of the emotional reaction of liking Shabbos. Rather the experience of Shabbos, the first-hand but internal to the mind qualia of Shabbos, that that reaction is based upon. It is as real and as objective as the experience seeing a ball. And just as I unquestioningly accept that a ball is red if I see that it’s red. I similarly accept the reality of Shabbos.

To extend this metaphor: What if many of us see the ball as red, but others, perhaps even a far larger group, insist they see it and it’s blue? Would their claims shake my faith in my own group’s perception, or would I trust my own eyes? (Assuming they work in general.) Why would the claims of another faith community (even the community whose faith is agnosticism or atheism) shake my belief in Torah?

Torah is based on first-hand experience of Torah, not on its “principles of faith”. My belief in those principles is because they explain that which was experienced, not the other way around.

Rabbi Prof. Shalom Carmy posted something similar to Avodah:

People who throw around big words on these subjects always seem to take for granted things that I don’t.

The people who keep insisting that it’s necessary to prove things about G-d, including His existence, seem to take it for granted that devising these proofs is identical with knowing G-d.

Now if I know a human being personally the last thing I’d do, except as a purely intellectual exercise, is prove his or her existence.

After all, aren't many parents capable of risking their lives for their children, or spouses for their loved one, over the same kind of experience of a relationship?

Along these lines, R’ Gil Student posted the following quote from Louis Jacobs, We Have Reason to Believe, pp. 25-26, 28-30 on Hirhurim:

Since Kant, these proofs [of God’s existence] have been heavily assailed…. Many theologians, nowadays, accept the validity of these refutations and admit that there can be no proof of God in the sense that there can be no proof of a mathematical formula… But they go on to remark that we can be convinced of a thing beyond of a shadow of a doubt by means other than that of mathematical proof. There is no such proof, for instance, of the existence of other human beings beside ourselves, yet we are convinced that they do exist… In other words a distinction must be drawn between proof and conviction — proof is one of the ways to conviction but there are other ways, too…

Many have arrived at this conviction as the result of a personal experience which convinces them that God exists. These men would rule out of court the very discussion of whether God exists, for, they would say, if a man is truly in love he does not ask himself if he is in love. The experience of God’s Presence is sufficient…

Other thinkers, again, hold that though each of the traditional proofs in itself is unconvincing, taken together they are convincing… Granted that the proofs carry no weight as evidence, they are indications and as such have the power of supplementing each other…

What it all amounts to is this, that while the existence of God cannot be proved if we start from the beginning, none of us do, in fact, start from the beginning. We are presented with two alternative beliefs about the ultimate reality and we have to choose between them. According to one view God exists–it is He Who created us, Who fashioned our minds and implanted the moral sense within us so that we are capable of recognizing beauty, truth and goodness and fighting ugliness, falsehood and evil. In this view the difficulty is how to account for the existence of evil. According to the other view there is no God… In this view the difficulties are how mind came from matter, how life emerged where there was no life before, how the universe itself came into being, how the good is possible of realization and how man came to strive for it–how man as a tiny part of the universe came to pass judgment on it?

Judaism neither stands on proof nor ought to be about proof. (In this approach. Obviously R’ Saadia Gaon, the Rambam, et al disagreed.) Rather, it stands on our having a relationship with Hashem and His Torah.

Answer 11

I disagree with how others The question should be why not believe in Judaism?

A G-d that is caring that sets forths laws and regulation to ensure that people are righteous. A G-d that does not punish others to an eternal hell. A G-d that does not have emotion, persuaded, afflicted with human emotions like other false gods (Greek Gods, Nordic Gods) A G-d that does not have this strange distinction between living in a society and the belief of finding "the truth or Nirvana" through starvation or separating oneself from society. The G-d of Israel is an eternal G-d that is unlike any other god. To not believe in a creator when there are righteous people on this earth. When you can see the beauty of mathematics, science, and etc. It seems to be silly. I think the OP should think keep in mind regarding the whole scheme of things about how almost every single society had a form of deities that created the world.

Answer 12

I think we are unable to prove any theory using only the instruments of the theory. I think this as a result of my understanding of Godel which is admittedly weak.

Here is an attempt to give some of the implications of Godel:

A theory rests on certain heuristics and these are to be considered but the theory that results from these heuristics doesn't have the tools to evaluate the heuristics. That is, the theory is incomplete. And every "sufficiently powerful" theory can be shown to be either false (that is it's heuristics are in contradiction) or is incomplete. So the fact that a theory cannot prove itself to be true is a good sign. Or atleast... It would be very bad if a theory could prove itself to be true. If a theory could prove itself to be true... we would know it to be false.

Answer 13

You can watch Rabbi Mizrachi’s famous video, Torah and Science. Link to the videos (Different Parts) Part 1:https://m.youtube.com/watch?v=RnO26XeIqGQ Part 2:https://m.youtube.com/watch?v=F-KnypPSOYU Part 3:https://m.youtube.com/watch?v=qrbJblAeVjc

B’H you will come to see that the Torah is truly 100% divine! Best wishes:)

Answer 14

I'd like to address a completely different issue - defining the TRUTH. It seems that the discussion jumped to conclusions without agreement on this term.

THere is a huge difference in the definition of the word "truth" between the religious vs the scientific world.

• The scientific world is based on the empirical, "de-Facto" truth (אמת מארץ תצמח) which comes from researching the available evidence.

• The religious world uses the theoretical, "de-Jure" truth, i.g "it is true because I said so" or "G-d said so" or Moses or else. Since one of the most important Mitzvahs in Judaism is following the sages, their sayings become "de-jure" true, no matter what the reality is. Remember the תנורו של עכנאי dispute, where the sages explicitly denied the "absolute G-d's truth" - "we rule our own reality".

Therefore from the religious point, Judaism will always be true, just because we/G-d/Moses/Sages/R' Ovadia Z"L said it is true. But from the scientific definition, it does not have to be true and Judaism does not pretend to be empirically true.

See Pesochim 94a, where R' Yehuda admits that the scientific approach sounds better than our Sages':

"תנו רבנן שנו חכמים: חכמי ישראל אומרים: גלגל קבוע ומזלות חוזרים וחכמי אומות העולם אומרים: גלגל חוזר ומזלות קבועין. וכו' אמר רבי: נראים דבריהם מדברינו שביום מעיינות צוננים ובלילה מעיינות רותחים"

The Jewish Sages say that during the day the sun travels beneath the firmament and is therefore visible, and at night it travels above the firmament. And the sages of the nations of the world say that during the day the sun travels beneath the firmament, and at night it travels beneath the earth and around to the other side of the world. Rabbi Yehuda HaNasi said: And the statement of the sages of the nations of the world appears to be more accurate than our statement. A proof to this is that during the day, springs that originate deep in the ground are cold, and during the night they are hot compared to the air temperature, which supports the theory that these springs are warmed by the sun as it travels beneath the earth.