In your language you have a form of poetry called the sonnet. It is a very strict form of poetry, is it not? There are fourteen lines, I believe, all in iambic pentameter. That’s a very strict rhythm or meter, yes? And each line has to end with a rigid rhyme pattern. And if the poet does not do it exactly this way, it is not a sonnet, is it? But within this strict form the poem has complete freedom to say whatever he wants, doesn’t he? …[In life] you’re given the form, but you have to write the sonnet yourself. What you say is completely up to you.
-Mrs. Whatsit, A Wrinkle in Time by Madeleine L’Engle