Metaphors and similes work through juxtaposition and are comparisons between two things.  Metaphors work directly through use of a verb (Tom is a mule) and similes by using  ‘as,’ ‘like,’ and ‘than.’  (Dan ran around like a chicken with his head cut off. Or Jane was quieter than a mouse.)  These comparisons help the reader to draw particular conclusions about the noun in question.  For instance, we might conclude that the main quality of a mule, “stubbornness” is shared by Tom, the erratic action of the chicken was shared by Dan, and the sounds made by Jane were in contrast extremely quiet if compared to a typically silent animal like the mouse.  For ease of discussion, and since both metaphor and similes work in the same manner, we will refer to both as ‘metaphor’. 

One of the reasons for using a metaphor is to highlight a particular aspect of an object and perhaps to bring a new depth of understanding to a poem or to suggest a new way of seeing a person or object.  Take for instance Wish for a Young Wife by Theodore Roethke.  Roethke refers to his wife as a “lizard” and  “lively writher” which serve to emphasize aspects of his wife’s movements.  The next metaphor addresses envy as “green ice” a nice twist, which ties into the lizard motif by suggesting that just as ice is a danger to a cold-blooded lizard so is envy to his wife.  Each of the metaphors, even the end one “When I am no-one” work to link the parts of the poem together thematically. The final image is of the lizard basking alone in the sun. 

By binding a poem together through a consistent way of seeing, the metaphors can help build the ‘world view’ of a poem. They can help define the boundaries of that view as large or small, abstract or concrete, real or surreal. The metaphors can help lead the reading of a poem.  Another way to use metaphors is as stepping-stones, each metaphor corresponding with the last yet making the connections in a slightly different manner, which can lead to surprising conclusions. 

Either way, take a moment to ascertain whether or not the metaphors in the poem work well when taken as a whole.  Beginning writers tend to include a hodgepodge of metaphors that work against each other.   Look at them thematically; if you have begun with a few metaphors comparing your relationship with your beloved to the ocean, stanza three is not the place to suddenly compare her to the refrigerator.  Remember as well, that the metaphors are never considered in isolation, but always in the context of the poem as a whole. What may be a fantastic metaphor may not in fact fit well into the poem at hand, cut it and remember to jot it in your notebook for later use. 

Just as it is easy to use too many adjectives or adverbs, a poem can be over modified by metaphors.  Check each one to assure that it sets down essential information and furthers the reader’s comprehension of the poem.  Some metaphors fall immediately into the category of clichéd writing.  Some are so common in usage that they are classified as “Dead” metaphors.  You should avoid these instantly recognizable phrases. (Easy as pie, green as grass, blue as the sky) 

While you are developing metaphors look for interesting juxtapositions that present an idea in a new way.   Yet, be wary, your first associations between two words may not always correspond to the readers’.  It is helpful to make a list of the possible connections between the two words.  Decide then if the important (to the poem) shared characteristic is one of the primary associations. This will help you determine if the metaphor does indeed work for the piece.  Be aware, there is also the possibility of a comical secondary association that may undermine a serious poem.  Yet, these comical associations can also be used to add a bit of levity into a poem, as in the Roethke poem above. 

Like salt in the sauce, judicious use of metaphors can add flavor to your writing yet if overused can make it unpalatable to the reader.  Take a moment to consider the metaphors in the poem, cut those that do not convey essential information, ensure that they flow smoothly from one to the next, and cut those that stick out like a scarecrow in the kitchen
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