Thoreau explains that the conscience need for Civil Disobedience
by pointing out that any person should fight and sacrifice for
what he or he believes is bias or unfair. And every conscience is
a driving force of anyone to fight and change everything that is
unfair in order to create a better,acceptable justice. He used the principle to justify his claim by mentioning the example of ending slavery ; he wanted to be justified only if the government is unjust and oppose the peoples' conscience.