According to Toynbee, "the essence of the Industrial Revolution" was "the substitution of competition for the medieval regulations which had previously controlled the production and distribution of wealth". Among its components were an "agrarian revolution" that produced "the alienation between farmer and labourer" and in the manufacturing world, the appearance of a "new class of great capitalist employers". "The old relations between masters and men disappeared, and a 'cash nexus' was substituted for the human tie." Summing up his interpretation, Toynbee wrote, "the "Wealth of Nations" and the steam-engine...destroyed the old world and built a new one." For Toynbee, this coupling seemed self-evident. Steam-powered factories, the "Wealth of Nations", competition, the cash-nexus and the rise of pauperism formed part of a single phenomenon.