Adam Smith defined how we think about free markets. His guiding principle was, famously, the invisible hand – a mystical force or the hand of God, but the idea that the pursuit of individual interests in economic life would inevitably produce an optimized and predictable economy. The theory rested on the assumption that individuals were rational in understanding their needs and thus in their economic actions. Government intervention would, therefore, disrupt the functioning of natural economic intercourse. For Smith, no overarching and or well-intended intervention in the free market could optimize the outcome of the economy; optimization is achieved only through freedom of action. Collectively, individual actions rationalized the system, propelled society forward and, crucially, provided predictability such that the irrational whims of the few had little impact on the whole.