Function
The hallmark of a poem is that it says much in few words. It can exist within a framework of prose, or it can exist on its own. Its chief function is to lend insight, poking its nose into unseen corners, sniffing out signs of life where none were detected before. A poem can evoke awe, inspire action or provide food for thought. It can provide an amusing escape (as in humor), or it can command solemnity (as in religious hymns). A poem can also function as an end unto itself.
Benefits
The benefits of a poem often begin where those of prose leave off. A poem can stretch the rules of grammar a bit more, using inventive line breaks or punctuation to accentuate a phrase. Poetry emphasizes the musical use of words for their own sake in addition to providing meaning and context. Brevity is another notable benefit of poetry.
Expert Insight
The celebrated American poet Edgar Allan Poe said, "Poetry is the rhythmical creation of beauty in words." He believed that a poem was there to be an aesthetic thing unto itself, not just a vehicle for some other agenda. On the mysterious and ineffable nature of what constitutes a poem, the poet-naturalist Henry David Thoreau said, "My life has been the poem I would have writ / But I could not both live and utter it." In other words, poetry has a life of its own.
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