In this talk from a 2018 'Marx in a Day' event, celebrating Karl Marx's 200th birthday and discussing his key ideas, Rob Sewell (editor of Socialist Appeal) explains the fundamental concepts of Marxist economics.
Rob touches upon the developments made by Marx from the ideas of his classical predecessors, such as Adam Smith and David Ricardo. In particular, Rob elaborates upon the labour theory of value and the origins of surplus value: the unpaid labour of the working class. By taking these theories to their logical conclusion, Rob outlines how Marx was able to explain the cause of capitalist crisis.