1. In case anyone is wondering, similes use "like" or "as." They suggest comparisons which also admit for difference. Metaphors are a more total connection between literal object and figurative meaning. The metaphor is also not incidental to the poem: it IS the poem.

2. Consider the difference between these sentences: "The mouth is/ one gate of hell" and "The mouth is like a gate of hell." The first line is a metaphor, and it's a far more evocative figuration than the second for a couple of reasons.

3. We not only see the mouth as an entrance to hell, we also get to imagine in what ways the mouth IS a gate to hell. We are also invited to imagine other body parts (I'll let you speculate) that also can cause hellish effects and behaviors.

4. The second line--which is a simile-- shuts down the complexity offered by the first line, because it merely compares. It says, in effect, speaking is sometimes kind of hellish. It's a poor rendition of the metaphor: it's less evocative, and it asks the reader to do LESS.

5. Metaphors, when they work, are the spine of a poem: why is THIS object that the speaker happens upon evoking a completely and seemingly different narrative entirely? It's because we see the truth of the world THROUGH objects. Simply put

6. poems are the ability to tell two totally different stories at the exact same time, while using the exact same language. Metaphors understand that: the things we see and experience become symbols for the story we are REALLY trying to tell.

7. That's why every word counts in a poem, and why metaphors--not similes, which are nice, but basically they are the doilies under your cupcake--become the working heart of the poem. We use both similes and metaphors within a poem, but you can't confuse their power

8. or treat them as equal literary effects, because they are asking readers to read in very different ways. End of rant. Thank you for coming to my TED talk.