Freedom of expression, which affords every person the right to voice his or her own opinion, ensures that no good idea goes unheard and that no bad idea goes unchallenged. Freedom of speech is a core political value, in that it ensures the right of the governed to criticize the government, and therefore serves as an essential check on state power. Further, classical liberals argue that open discourse is essential to learning and to the seeking of truth. It’s crucial for people to have conversations with those they disagree with in order for each to discover where his or her prior ideas are wrong or incomplete. Even engaging with totally false claims can sharpen and improve one’s own argument and understanding. With that said, freedom of expression does not guarantee that discourse will always be productive. Classical liberals recognize that certain cultural norms of conversation and debate, such as the presumption of good faith, respect for reason and evidence, and intellectual humility, are essential companions to freedom of expression if conversation is to lead to learning and discovery.