"Capitalism is not necessarily more immoral than previous social systems with regard to cruelty to humans and the gratuitous destruction of nature. As a mode of production and a social system, however, capitalism requires people to be destructive of the environment. Three destructive aspects of the capitalist system stand out when we view this system in relation to the extinction crisis: 1) capitalism tends to degrade the conditions of its own production; 2) it must expand ceaselessly in order to survive; 3) it generates a chaotic world system, which in turn intensifies the extinction crisis."