(i) Full employment : An industrial society based on mass production cannot be sustained without mass consumption. But to ensure mass consumption, there was a need for high and stable income Income could not be stable if employment was unstable Thus, stable income also required a stead. full employment. (ii) Intervention of government : Before the Second World War, most of the economists believed that capitalist economies or markets are self-sustaining. i.e. there is no need for government intervention. But the inter-war period proved that markets alone could not guarantee full employment. Therefore, the government would have to step into minimise fluctuations of price, output and employment. Economic stability could be ensured only through the intervention of the government.