There is no such a thing as a next number. What do I mean by that? Let's use 1 as an example. 1 does not have a number that is next to it. You might think 2 is the next number, but 1.5 is actually in between them. The next number becomes interesting. Suppose you a have a inch piece of wood. Now let's look at it's half-point. It's half-point is 0.5, what comes next? It should be whatever is next to it, but there is nothing next to it. No matter what other length comes after it, there will always be a smaller length before it. Let me get more in-depth. Suppose, after the 0.5 point of the wood, the next length is 0.6. That means 0.6 came before 0.55. It can also mean that the length 0.55 does not exist.