Elements for a coherent theory of rent

The question of rent in economic theory is rather complicated, even at the level of its definition. This article attempts to get back to basics in order to clear things up and present a complete and correct theory of rent. Starting with the classical definition of rent, as an income earned by the owner of non-produced inputs, it clarifies first the definitions of the different kinds of rent: differential rent, absolute rent. It then uses a step-by-step approach to show the effect of these various kinds of rents on a price system. The article also addresses the issue of type II differential rent, corresponding to the use of different techniques with a homogeneous input. This helps to explain the effect of rent on the distribution of the product. The question of urban land rent is also clarified: it is shown that it obeys mechanisms that are clearly different from those governing agricultural land rent.