Nothing can more obvious than this. It's even hard to imagine that in any text, for example in this very one, there is no other text, because with no doubt another text can be composed from the letters that are used in this text. In fact many different texts can be composed.
The point is a writer (and a reader) should make the most of this fact consciously and on purpose.
For example: let's write a text in such a way that the first (or second, or third, or fourth, or the last) letters of the words would give us another text. Or the first letter of the first word and the second letter of the second word and the third letter of the third word and the fourth letter of the fourth word and the fifth letter of the fifth word and if the fifth word doesn't have five letters then the first letter of this word and then the second letter of the next word and so on would compose themselves into another text. Or red letters compose themselves into a red text, blue letters into a blue text, green letters into a green text, of course when the words were printed in colours – black letters together with the colour ones would give us the basic text.... Or the words could be read like a knight moves across a chess-board.... And so on.
Certainly, the chosen letters not necessarily should be composed into texts – they could create signs, symbols, even pictures.
But what a hell is the reason to make simple things so complex? Because the world is a hell complex. Yes, the world is fucking complicated.
So, why a hell do we want to make it more complex? Shouldn't we try to make it less complicated?
But if we want to understand the world, we must understand its complexness – simplified models will not help us, maybe even hamper our efforts to understand it, and thus make everything even more complicated..... Nevertheless we should keep moderation. What is simple should stay simple, should be reflected and presented in a simple way. How can we separate simple things from the complex ones?

With a line. A dotted one, for example: