The “Loi du debit”

Cournot thinks that the relationship between the price and the quantity produced - the “debit” - cannot be established theoretically. The law of demand is empirical and must be based on observations. He just supposes demand to be a generally decreasing func­tion, f(p), of price. The demand of a small number of agents is a discontinuous function, but, when dealing with a great number of agents, it is possible to consider it as continu­ous and that its variations are proportional to those in prices when they are small com­pared to their initial level.