Marxian economics or the Marxian school of economics is a school of economic thought that traces its roots to the critique of political economy first expounded upon by German philosophers and economists Karl Marx and Friedrich Engels. Marxian economics concerns itself with the analysis of capital accumulation, origin of economic crises, exploitation and the process of socioeconomic transformation. Marxian economics draws upon a wide variety of Marxist and non-Marxist sources and has many different, sometimes conflicting variations and branches.