Now to start I want to point out that this answer is in the "Kids Answers" section on Ken Ham's webpage. Thus the answer is being addressed at those who might not have the necessary knowledge and tools to analyze the answer. To me this makes Ham's answer that much more foul and insidious. However, I have to say that I bet that a lot of kids could even see the glaring logical problem sitting in Ham's answer.
Ham uses three prominent logical fallacies to prove his point: non-sequiturs, circular logic, and false statements. But let me start with a brief description of Ham's answer to why other religions aren't true and then I will give examples of each of the fallacies Ham employs.
Ham's argument essentially involves three different types of claims to show that religions other than Christianity are not true. First he states that the bible tells us about things like the origin of life and where we came from. Second he claims that no other religions have books that do this. Thirdly he just says that any religion is false if it isn't Christianity.
Lets look at a quote from Ham:
No religion other than Christianity has a book like the Bible that tells us about the origin of everything, and who we are, where we came from, what our problem is (sin), and what the solution to our sin problem is. No other religion has a Savior who is alive (He rose from the dead). All other religions require people to do something to work out their future—only Christianity has the solution that we can’t save ourselves, only God can do it.In this quote Ham simply tells us a few things that the Bible says. However, just because the bible says those things does not mean they are true. For example, just because the Bible tells a story about how everything originated doesn't mean that story is correct and that other stories are wrong. Imagine someone claiming that the story of Rudolph the red nose reindeer proved Santa Clause existed. No one would take that claim seriously just as no one should take quoting the bible as serious evidence of its truth. Remember, having the ability to tell a story about something does not make that story true.
This is called a non-sequitur, an argument that even if true does not prove his point. Ham has argued that his book tells stories such as the origin of everything. But the fact that his book can tell stories doesn't prove that his religion is the only true religion. Simply stating what his religion believes is not sufficient to prove that it is true. He must produce positive evidence that supports his position.
Circular logic is an argument that depends on its conclusion as a premise. Circular logic is easy to see if you put someone's argument into a set of premises and conclusions. Lets take Ham's argument: "if [other religions] don't believe in the Bible they are not true."
Here Ham essentially claims that the bible is true and therefore any religion that doesn't believe in the bible is false. But remember the exact question Ham is trying to answer is whether his religion is true! You can't prove that something is true by simply saying it is true. Thus, Ham can't prove that his religion is true and others are false simply by saying over and over again that it is true.
This is a perfect example of circular logic. Ham believes his religion is true and others are false because he believes his religion is true. I find it hard to believe that Ham could have seriously made an argument this obviously bogus without either being an idiot or dishonest.
I first want to point out that I don't accuse Ham of lying because lying requires knowledge that what one says is false. Although, it seems that anyone would know the things Ham states are untrue I do not know if he actually thinks he's telling the truth. Thus, I do not accuse him of lying, just accuse him of stating blatantly false things.
Ham's false statements are so obvious that I'll just point out one real quick and leave the rest for you to find. First Ham says that "no religion other than Christianity has a book like the bible that tells us about the origin of everything . . . ." Um, many other religions do have books that tell us about the origin of everything take for example pastafarianism.
Go ahead and look at his other claims about the uniqueness of Christianity. They are all pretty much false because other religions claim the same things.
As a closing interesting note lets take another look at Hams answer. Ironically Ham actually proves himself wrong in his answer. As discussed above other religions make claims just like those made by Christianity. If having an origin story was enough to make a religion true then every religion would be true by Ham's standards. If I were a kid reading that answer I would question my religion even more afterward.
Even though Ham's argument may cause some kids to question their religion more his argument is still reproachable and dishonest. Kids do not always have the knowledge necessary to understand poor arguments. Thus using clearly dishonest arguments to answer a child's answer is a disgusting technique. But even worse is that Ham is teaching kids bad logic. Children are likely to listen to adults and believe them, especially adults they might look up to like Ham. When Ham uses poor arguments he is giving legitimacy to bad argumentative techniques and thus doing a disservice to these children's education.