Thomas Robert Malthus
A notable current within classical economics was underconsumption theory, as advanced by the Birmingham School and Thomas Robert Malthus in the early 19th century. These argued for government action to mitigate unemployment and economic downturns, and were an intellectual predecessor of what later became Keynesian economics in the 1930s. Another notable school was Manchester capitalism, which advocated free trade, against the previous policy of mercantilism.