Already in ancient times, philosophers debated the nature of happiness and the recipes for a happy and fulfilling life. Today this question is also hotly debated by scientists and politicians, who are particularly interested in what can be done to increase the happiness of their voters (and citizens, more generally). Happiness has become so important nowadays that four countries: Bhutan, Ecuador, UAE, and Venezuela went so far as to employ ministers of happiness!

The existence of a sizeable shadow (or second, informal) economy in the USSR was and is well-known. The Soviet era was characterized by a very rigid formal system with a high level of bureaucratization and inefficient planning. This resulted in many problems, both in terms of production and consumption. Soviet consumers experienced constant frustration and dissatisfaction caused by endlessly searching for goods and services they demanded, the need to queue for them without any guarantee of getting what they wanted, and the risk of having instead to accept a lower quality version or even to postpone (sometimes indefinitely) the purchase altogether (Kornai 1992).