The macroeconomic concept of human stupidity proposed by Carlo Cipolla in 1976 allows assessing the impact of a group of people with destructive behaviour on the trajectory of economic growth. The purpose of the study is to build a macroeconomic theory of destructiveness through formalising the participation of two social groups – stupid and intelligent people – in the national economy. The methodology of the research consists in extending the theory of production function to the heterogeneous population of a country, which splits into two qualitatively heterogeneous social groups according to their behavioural properties. The research method resides in formulating a dynamic production function taking into account the structure of the population to obtain a differential equation of economic growth, which allows establishing the properties of the simulated system. The resulting economic growth equation reveals the critical proportions of stupid individuals for local and global regimes of development. In the first case, the growth of per capita GDP is disrupted, while in the second, the growth of GDP is bruised. An analytical study of the constructed model regimes establishes the property of the minimal rationality of society, according to which, in order to maintain the regime of macroeconomic efficiency, intelligent people must ensure for themselves some minimal influence in the management and production system. The constructed model can have three equivalent interpretations – the macroeconomics of stupidity, errors, and harm. The first interpretation considers two types of economic agents, with rational and irrational behaviour, the second – successfully or unsuccessfully resolved tasks, and the third looks at the joint action of the population conducting creative activities to increase GDP and cohorts of saboteurs engaged in counterproductive work to disrupt public order and damage the national economy. Such an expansion of the original model makes it possible to move on to a generalised interpretation in the terms of macroeconomics of destructiveness.