What has attracted me most to libertarianism – next to the Non-Aggression Principle – is its attitude towards our knowledge which can be described as epistemologically modest. Epistemology is a branch of philosophy that is concerned with our knowledge: how do we know what we know, what is the nature of our knowledge, what is its scope, and what is justified belief? Libertarianism is modest in the sense that it promotes an awareness of how little we know about the social forces in our society, and what the particular consequences are when certain social forces are at play.
In ‘The Pretense of Knowledge’ (1974), Friedrich Hayek had given an excellent account on the libertarian epistemological modesty. He writes that when policy makers are epistemologically immodest – meaning that they unjustly believe that they truly understand the social world to the extent that they can plan or direct certain social forces to achieve certain ends – they will do more harm than good in their efforts to improve the social order. Hayek argues that each individual knows just a fraction of what is collectively known. Since knowledge is decentralized and each individual has unique information with regards to his or her particular circumstances, it is best to leave those with local knowledge to take decisions on how to plan their lives. Unfortunately, many do-gooders ignore Hayek’s advice and attempt to plan and control society. The dangers of epistemological immodesty are visible all around us. Take for example the NATO-led war campaign against Gaddafi in Libya in 2011. The meddling with Libya’s internal affairs has led to many unintended consequences that were totally unforeseen by most politicians: in a country that was previously relatively peaceful, manifold precious lives have perished, many have been wounded, many children have become orphaned, millions of people are trying to flee the civil war and to find refuge in other countries, ISIS has taken control of several parts in Libya, and terrorism has now become more widespread. Politicians who believed that they knew enough about the social forces in Libya, and how they could overthrow Gaddafi and turn it into a peaceful democracy have been dead wrong.
The epistemologically modest libertarian knows that military, economic, and political interventionism, always leads to unintended consequences. It is therefore best to refrain ourselves from such interventions as much as possible. This anti-planning sentiment had been graciously expressed by the American physicist Robert Oppenheimer when he discussed world affairs:
It is perfectly obvious that the whole world is going to hell. The only possible chance that it might not is that we do not attempt to prevent it from doing so.
 I cannot verify the authenticity of this quote. It was attributed to Robert Oppenheimer by Alan Watts.