Variety,growth and demand

A dynamic model of demand compatible with a changing composition of the economic system is presented in this paper. Consumers are not expected to have completely formed preferences for radically new objects of consumption. Consumers adopt new goods or services ,created by innovation, only if three barriers are overcome: 1) a critical (minimum) level of income, 2) critical human capital, 3) critical fitness. However, even a new good or service with a fitness higher than that of pre-existing ones, will not be immediately adopted. Consumers'.limited knowledge will slow down the rate of adoption of any new good or service.