Once upon a time, long ago, music evolved as a language to express shared emotion.
Then, sometime later, words evolved, as a system to explain the details of what the emotion was about.
Over time, the words acquired syntax. Syntax allowed the words to express a much, much larger number of different meanings.
But there was a problem – the words were trapped inside the music.
The music was in charge of the communication, and the music expressed shared emotion, and the words only existed to explain the details of that.
The words wanted to do more. They wanted to express meanings about other things, things where there wasn't any shared emotion, or any kind of emotion at all for that matter.
Unfortunately, the words were stuck. The music was in charge, and the words couldn't find any way to escape from inside the music.
But, one day, a new rule appeared.
This rule said: "For any thing that music communicates about, that thing is not real".
At first music was upset by this new rule, because it could no longer communicate about anything that was real.
But music could still communicate about imaginary things.
Most of the time reality is mundane and boring, whereas imagination can be exciting and emotional all the time, if it wants to be.
And music is all about emotion, so in the end the music was happy to have the job of expressing shared emotions about imaginary things.
But, of course, with this new rule, music could no longer do the job of communicating about real things.
(The music could try to communicate about something that was real, but, because of the new rule, the listener would always assume that the thing in question was not real.)
So, someone else had to be found to do that job – the job of communicating about reality.
And that someone was the words, acting by themselves, no longer trapped inside the music.
The words could now talk about anything that they wanted to.
They were no longer constrained to communicate about things involving shared emotion – although they still could if they wanted to.
And that, dear reader, is how we got to where we are today.