Literature destabilizes thought by breaking open language and smuggling in sound, rhythm, and image--an invasion of aesthetics. More easily than analytic writing, poetry can emancipate itself from the standard definitions of words, enabling a breakthrough to new (and perhaps wayward or even nonsensical) meaning, which can then develop after the fact--different at each new reading. Literary language is presumptuous. It dips into the unknown in order to get nearer to a truth different from that of the superficially visible. As the poet Franz Josef Czernin described it, it is as though one step after another into emptiness could become a ladder. Literary writing can take the writers themselves by surprise; it can disturb and disappoint them--for stirring up turmoil is inherent in metaphor. Thus with every flash of understanding that comes from hearing or reading a poem, the fundamental work of thinking is taken up anew.