Those with a belief in open society base the demand for liberty on the recognition of human ignorance; we need to be free because we are ignorant and fallible. Free social cooperation permits us to mobilize our knowledge and develop methods of discovery through which we can explore the unknown and continually correct our errors. To assent to free cooperation is to accept critical discussion, democracy and the market and in this way we are able to increase our rationality and further political and economic development.

Improvement in the conditions of our lives, therefore, does not come from the omniscience attributed to some enlightened legislator or planner. Ignorance and Liberty examines how the market is a place which liberates us from this idea of a privileged source of knowledge. The market is not only a place where goods are exchanged but also where different philosophical ideas and religious beliefs must co-habit, opening up new horizons and undermining the sense of an absolute that prevails in a closed world.