Background: Happiness and its determinants have been the subject of scientifi c inquiries as early as in the works of Aristotle. It has appeared in many fi elds of science. For example, in economics, Frank Knight indicated happiness as one of the three main factors of business success (1921). Nowadays, positive psychology also deals with success. Happiness is therefore an important success factor, not only in business, but also in the real life, career, and development of every human being (Brickman et al. 2016; Seligman 2005). Aim: The main research problem, as a case study, was to identify a defi nition of happiness, which would provide the opportunity to formulate a mathematical model, thus making it possible to measure levels of happiness. Materials and methods: Literature reviews on the defi nition of happiness were conducted to achieve the main aim. They resulted in identifying the proposals of Stanisław Lem, who in his futuristic works not only off era definition of happiness but also describes a unit of its measurement and provides a recipe for it. This became the basis for designing a computer simulation of the defi nition of happiness as a kind of human experience. Results: A newly designed mathematical model was formulated that describes levels of happiness from a quantitative point of view, including a unit of its measurement. Conclusion: The designed mathematical model is complete and is the fi rst example of the implementation of the defi nition of happiness described in literature. It is also the first step in the mathematical approach to happiness becoming the most important factor of human work, development, and success.