In "On Civil Disobedience," Thoreau talked about the problem with social institutions, and stressed that people must first listen to their conscience and then look at rules. Thoreau believed that people were putting the laws first, and this was how social and political atrocities such as slavery came to be.
One of the larger arguments in the essay is that government is almost always unhelpful and unjust. Thoreau argued that those who are in the majority will always hold the power because they outnumber the others. This majority thought or opinion would then become the thought that is legitimatized. Thoreau did not want people to feel obligated to follow this majority opinion. He wanted people to recognize that their first duty should be to their conscience and to what was right.
Thoreau does address the idea that not everyone needs to try to fight the "wrong" or the "evil" in the world. However, he firmly states that everyone has a duty and an obligation not to be someone who is part of the "wrong" and the "evil" in the world. Throughout the rest of the essay, Thoreau covered world topics at the time with his own social commentary. He also included poems.