Thoreau uses mode of discourse and chose to write it in argumentative form. He chose to go against the goverment and stay true to his own belief system. Thoreau agrees with the qoute "The goverment is best which governs least." Thoreau agrees that no goverment is the best way to go. Thoreau believes the goverment will destroy itself from within due to the fact that they will begin to go against each other, because they do not have the vitality and force.
Thoreau adds imagery to get his argument across