Karl Marx invested 30 years on Das Kapital, which went on to become a magnum opus. Kapital was based on years of studying capitalism in England, which was the most advanced industrial society in Marx's time. He arrived at a complex theory on structure and function of capitalism on the basis of that. Driven by an economic urgency, he talked about the nature of commodities, wages and work-capitalist relationship amidst a barrage of other related issues. His focus remained on presenting the nature, development and future of the capitalist system.