Schumpeter's most popular book in English is probably Capitalism, Socialism and Democracy. This book opens with a treatment of Karl Marx. While he is sympathetic to Marx's theory that capitalism will collapse and will be replaced by socialism, Schumpeter concludes that this will not come about in the way Marx predicted. While Marx predicted that capitalism would be overthrown by a proletarian violent revolution, which historically actually happened in the least capitalist economic countries, Schumpeter instead believed that the capitalist system would collapse as a result of an internal conflict that bolstered hostilities among itself. To describe it he borrowed the phrase "creative destruction", and made it famous by using it to describe a process in which the old ways of doing things are endogenously destroyed and replaced by new ways.