This article by an atheist (let's call him "Quark") proportedly lays down an "unsolvable" puzzle. I would normally ignore such trivial pursuits, but Quark also claims that his puzzle's 'unsolvability' has implications for the existence of God. As such, a gauntlet has been thrown, and I accept it. I will see if I can solve the unsolvable (something we pesky Christians always try to do).
The article is short, but I'll still give a summary. There is an old logic puzzle that asks, "If you came to a crossroads and didn't know which way to go, and two men were standing at the same crossroads, and you knew that one always lies and one always tells the truth, and you can only ask one question to these two men, what one question could you ask them to ascertain the correct way to go?" Somehow, the atheist who wrote this article uses this logic puzzle to "prove" that there is no way to know which religion is right and which one is wrong because (according to him) once you add more liars to the mix, the logic puzzle becomes "unsolvable," i.e., there is no way to tell who is the truth-teller amongst all the liars. I would like to try and solve it if I may (as well as point out a few criticisms).
Quark correctly asserts that the one question you can ask to solve the puzzle is to ask, "Which road would he tell me [is the right way]?" In this scenario, the two men are forced to answer the way the other one would answer. Thus, the liar will lie about the way the truth-teller would say, and therefore say the wrong way; likewise, the truth-teller would truthful tell the way the lair would recommend, which is also the wrong way. Therefore, you would go the opposite direction they both mentioned. So far so good.
Quark goes awry, however, when he claims that adding more liars to the mix (making the lie-truth ratio 4-1) makes the question "unsolvable." You can determine, even in this scenario, who is telling the truth and who is not, and you can do it by asking them all the same exact question: "Which road would they tell me to take?" It works slightly different than before, but the result is the same. It works like this: the truth-teller is the only one who will say that the four other men would say the same thing; conversely, the liars will always say that three of the other men would say the same thing but one would be different.
Remember: according to our scenario, there are still only two ways to go, with only one way being right. The possible lies and truths available to the liars and truth-teller are limited to only two responses: this way or that way. Consequently, the liars will all be in agreement with there answer (because they all lie), but the truth-teller will be the lone dissenter (because he alone tells the truth). Thus (as said before), if the man you ask answers that all four of the other men would say the same thing, you know that you are dealing with the truth-teller; likewise, if the man you ask answers that three of the men would say one thing and one would say another, you know that you are dealing with a liar. Paradoxically, the liar cannot lie about the truth-teller's dissension; if the lairs are saying one way, but the truth-teller another, and there is only two ways to go with only one being right, then no matter what a liar says, he will always have one of the other four as being different.
The result is that you know who is who, and thus you can navigate your decision: whatever the truth-teller says about the other four, you should go the opposite way (because he is truthfully telling what the liars would say, which is a lie); whatever the liars say (watch this!), you should follow whatever direction the liar says that three of the four men say because he will lie about what the liars would say and thus tell you the truth (of course he will lie about the truth-teller, who you will recognize because he is the only dissenter)! Liars lying about liar's lies and thus telling the truth; as you can see, Quark was dead wrong when he said the scenario was "unsolvable". Quite the contrary, the puzzle actually becomes easier, because you will easily know who is who and which way to go because the liars will lie about the other liar's lies and thus tell you the truth (which you will be able to identify). In addition, this scenario can work no matter how many liars you insert, because you can always identify the truth-teller as the lone dissenter (and the liars will always lie about liar's lies, etc.). Thus, I have solved the "unsolvable" puzzle. Since I obviously won't be getting a cookie for my efforts, I will move on to my criticisms.
Quark makes a logical snafu when he tries to apply his "unsolvable" scenario to world religions. First of all, the scenario is no longer "unsolvable." It is actually easier to solve. Thus, his hopes to use his unsolvable puzzle for atheistic purposes are utterly dashed, as his original scenario no longer works for his purposes.
Second of all, however, even if the original scenario was indeed "unsolvable," it would still not apply for one small yet vital reason: in the original scenario, there are only two paths with one right way; in the world religions analogy, however, there are now multiple paths with only one right way. Since the structure of the puzzle has fundamentally changed (for the number of paths is key to the puzzle), any applications made in the original puzzle cannot apply to this new analogy because this new analogy is based on a completely different puzzle: the puzzle has changed from a two path/one right way structure to a multiple path/one right way structure. This analogy has introduced a scenario that is fundamentally different from the original scenario, and thus Quark's attempts to apply the original scenario to this new scenario is erroneous.
Let's look at this new puzzle laid down by Quark: "Imagine we replace the town [you are trying to reach] with Heaven, and replace the men with a Hindu, a Buddhist, a Jew, a Christian and a Muslim, and add a road for each. How can you determine who is telling the truth and who is not?" Quark's solution? "All you can do is just pick a direction and go." What's his conclusion then? "That doesn't seem like something that was set up by the supreme intellect in the universe. That strategy violates the principle of minimizing as much uncertainty as possible to increase the likelihood of a successful outcome."
Now, the short (and Christian) answer to the puzzle is that God is not only there (i.e., He exist) but is also not silent (i.e., He has made Himself known). Aside from general revelation (i.e., creation [Romans 1:19, 20] and mankind's "mannishness" [Romans 2:12-15]), there is special revelation: the word (i.e., the Bible) and the Word (i.e., the Incarnation [John 1:1, 14; Hebrews 1:1-4]). Not only did God drop signs of His presence in our world and in ourselves, He also wrote a book and came down in person to tell us that He is there and all that He says is true. In Quark's scenario, this is the equivalent of the owner and founder of the town coming down to you and telling you, "That's the right way." Then he leaves you his notes on the subject so you do not forget what He said. This same scenario can not only answer this multiple path/one right way scenario, but also the "black box" scenario (i.e., you can know what is inside the impenetrable box if what is inside the box  is there, and  is not silent).
Of course, atheists will claim, "The bible is full of errors!" "Jesus never existed!" "The Bible's claims have been disproved!" "Jesus was not God!" That is my point, however. I have just spent the last few paragraphs solving an "unsolvable" logic puzzle that could be applied to world religions only to find that the whole atheistic argument here was not about a logic puzzle or world religions at all; this was about Christ and the Bible. Quark's world religion scenario is unsolvable only if you assume that Christ and the Bible (as well as creation and man's humanity) are discounted from the get-go. It sounds like Quark is doing a new thing, but he is not. He is simply dressing up old issues in new clothes, clothes that do not fit or even match. His "unsolvable logic puzzle" is mere subterfuge disguising the real issues, which are Christ and the Bible, not the presence of world religions against the reality of God; if Christ is God and the Bible is true, then the presence of world religions is irrelevant in regards to the reality of God.
To my fellow believers, remember: to be an engaging, critically thinking Christian means you hear the issues behind the issues. Atheists will mount what seems to be innumerable arguments against your faith, but do not be fooled; they are merely blowing smoke to cover the few real issues that they actually have. The real issues are were the battles must be fought, and atheist's smokescreens will only serve to cloud the issues from you. You must learn to disperse such clouds.