Augustin cournot and neoclassical economics

This paper compares Cournot's exposition of elasticity of demand and the theory of the firm with modern exposition. In the case of the theory of the firm, this comparison is accomplished by translating the modern textbook exposition into Cournot's mathematics. It is demonstrated that Cournot's exposition translates into current usage in all cases but that the degree of convolution in the translation process varies from case to case. For elasticity, only trivial algebraic manipulation is involved. For monopoly, the inverse derivative rule translates Cournot's exposition into current usage. With regard to oligopoly, Cournot provided, in a different contest, the analytical structure that is now used in IO to analyze differentiated oligopoly. It is reiterated that Cournot had a general method for finding equilibria for non-cooperative games and was aware of the fact that his method was more general than a single application. The relation between Cournot equilibria and Nash equilibria is discussed.