Imagination

Our speaker has one heck of an imagination. And it makes for some really cool combinations of ideas in his description of his surroundings. That imagination could also be part of the reason for his discontent. If he didn't have such a good imagination, he might never have supposed there was another way to live. Nor would the life of the men in his book seem so vivid and awesome.

• Lines 1-3: The poem opens with a metaphor, or rather two metaphors: Kansas is a concept, and Kansas-concept is a checkerboard design of wheat and corn. The way this metaphor rolls on and complicates itself is cool work of the imagination because it allows our speaker to give us a conceptual and visual metaphor for the distance between him and the state below.
• Lines 4-5: But our speaker isn't done yet. He goes on to add a simile comparing the checkerboard design to a page in his neighbor's magazine. This adds yet another dimension to the description, and gives us a better idea of the way the world below seems small and insignificant. Now that's some imagination.
• Lines 34: Repeating "Imagine" at the beginning of two sentences in a row is anaphora, and it helps establish some linguistic momentum. Our speaker is building up this imaginary scene, and repeating that word is like a little tug, pulling us closer and winning us over. 
• Lines 34-36: This simile sets up the idea that modern life is like spending your whole life in a single room. And calling it a room reminds us of the way that kind of life can be cut off from the world and from certain kinds of feeling. And imagining a century like a large room makes us think of that century very differently. It makes it like a room that we breathe in, walk around in, which, when we think about it, sounds just about right. We mean, you're sitting right in the beginning of the twenty-first century, reading these words.