Ah, how often I've cursed those foolish pages, That showed my youthful sufferings to everyone! If Werther had been my brother, and I'd killed him, Hi… - Johann Wolfgang von Goethe

All poetry is supposed to be instructive but in an unnoticeable manner; it is supposed to make us aware of what it would be valuable to instruct ourselves in; we must deduce the lesson on our own, just as with life.

You can’t, if you can’t feel it, if it never
Rises from the soul, and sways
The heart of every single hearer,
With deepest power, in simple ways.
You’ll sit forever, gluing things together,
Cooking up a stew from other’s scraps,
Blowing on a miserable fire,
Made from your heap of dying ash.
Let apes and children praise your art,
If their admiration’s to your taste,
But you’ll never speak from heart to heart,
Unless it rises up from your heart’s space.

A teacher who can arouse a feeling for one single good action, for one single good poem, accomplishes more than he who fills our memory with rows on rows of natural objects, classified with name and form.