Under feudal monarchism, a merchant class or bourgeoisie began to emerge. Modern liberals and conservatives are derivatives of classical liberalism, though some elements of classical conservatism may be found in modern organic conservatives. Classical socialism has its roots in the egalitarianism of Christianity and fears of social Darwinism. The two primary challenges to western ideology and political systems are fascism and environmentalism. Fascism is an extreme form of nationalism, symbolized by Nazi Germany, that combines elitism, militarism, organicism, anti-intellectualism, and authoritarianism.
Environmentalism is concerned with protection and promotion of the bioshpere.
Originally environmentalists were either conservationists or preservationists. Recent concerns over pollution, overpopulation, ecocide, resource depletion, and dangerous new technologies have resulted in a worldwide environmentalist movement concerned with establishing a sustainable society. More critical thought is typically required than in other subjects. Evidence seems to be selected at face value to support a specific point, without diligent fact checking. He is never mentioned when discussing the concepts of international trade and comparative advantage.