When I heard the learn'd astronomer,
When the proofs, the figures, were ranged in columns before me,
When I was shown the charts and diagrams, to add, divide, and measure them,
When I sitting heard the astronomer where he lectured with much applause in the lecture room,
How soon unaccountable I became tired and sick,
Till rising and gliding out I wandered off by myself,
In the mystical moist night-air, and from time to time,
Looking up in perfect silence at the stars.
This poem reminded me of "Introduction to Poetry" by Billy Collins. I think it portrays a similar theme. As a Physics students, I have had some lessons on the theorems and mathematics behind the stars, though probably not even scratching the surface of what this "learn'd astronomer" taught. All the same, I can testify with this poem: it gets tedious. On the other hand, I have been in the desert or the mountains at night, far from civilization, and looked up at the pure expanse of endless pinpricks of light. While being about the do the math makes you look smart, there's no feeling quite looking at the clear night sky. That beauty is not something you can capture with numbers and equations.
I like the way Whitman has set up this poem. His first four lines all start with "When." The first sets the scene, the second adds detail, and so it goes, getting longer and longer, until the fifth line, where he finally picks up again with the sentence. It seems that Whitman is imitating the astronomer's lecture. Originally interesting, it drags on and bogs down in details. I particularly like how each line gets longer, expressing Whitman's frustration. It is especially powerful in conjunction with Whitman's ironically positive diction. He never directly insults the astronomer and even says that "he lectured with much applause." Whitman calls his tired and sick reaction "unaccountable." But it couldn't be clearer that he never actually meant the praise when compared to his words in the second half the poem. Sweet, graceful words like "gliding," "mystical,""silence," and "stars" express true emotion unlike the accurate but empty words of before. They express a sense of release -- and not just from the astronomer's lecture.
Whitman is not insulting the astronomer. If he were, his tone would be much more sarcastic. But he expresses a sort of detachment from the astronomer and his audience. It seems that Whitman has found himself in a crowd that he does not -- cannot -- relate to. He watches the astronomer demonstrate impressive things, watches other people erupt in applause, but he remains untouched. It seems he leaves, not just out of boredom, but out of loneliness. He seems to think through how he sees the stars so differently than everyone else. He does not attempt to describe the stars, even in their beauty. The obvious point of the poem is to criticize those who analyze to the point that they loose the true value of a subject, but there is also an underlying theme of a man who doesn't connect with the excitement of the people surrounding him. Because an appreciation for the night-time sky isn't something that can be shared in a lecture. There is a sense of loneliness and isolation to the poem because of this disconnect. The emotion heightens the reader's sympathy for Whitman, and in the end, re-enforces the idea of true experience being cluttered with data. It's an ingenious poem.