Factors of production

A categorisation of the production process that was adopted for didactic purposes by classical economic theorists divides the contributory factors into the "primary factors" of land and labour, that exist independently of economic activity on the one hand, and capital (economics) on the other hand, defined as a product of economic activity that is used to further such activity. Later theorists have found it useful to depart from that categorisation by recognising that social capital and human capital make contributions to production that are analagous to those of classical capital although they are not products of economic activity.

As explained in the article on the philosophy of economics, economists' statements about the factors of production are tautologies rather than factual statements about the real world.