Answer:
One possible theme of the night that Thoreau spent in jail, as described in his essay "Civil Disobedience," is the power of individual conscience and the importance of standing up for one's beliefs. This theme is evident in the following quote:
"I did not for a moment feel confined, and the walls seemed a great waste of stone and mortar. I felt as if I alone of all my townsmen had paid my tax. They plainly did not know how to treat me, but behaved like persons who are underbred. In every threat and in every compliment there was a blunder; for they thought that my chief desire was to stand the other side of that stone wall. I could not but smile to see how industriously they locked the door on my meditations, which followed them out again without let or hindrance, and they were really all that was dangerous" (Thoreau, "Civil Disobedience").
In this passage, Thoreau reflects on his experience of being jailed for refusing to pay a tax that he believed supported the unjust Mexican-American War. Rather than feeling confined or distressed by his situation, Thoreau finds a sense of freedom and fulfillment in standing up for his beliefs and acting in accordance with his conscience. The "townsmen" who locked him up and tried to suppress his thoughts are depicted as "underbred" and misguided, suggesting that Thoreau sees their actions as lacking in moral character. Overall, this passage supports the theme of the power of individual conscience and the importance of standing up for one's beliefs.
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