SummaryNeoclassical economics is really the birth of mathematics as an inescapable tool for constructing theories that are internally coherent (that is, explained in and of themselves without requiring casuistic examples), escaping the slightly lackadaisical approach of many classical economists like the great Ricardo. This allowed Economics to develop at a much faster pace, and provided the basis for how Economics is studied and investigated today.
Jevons was a British economist (1835-1882), who is considered, along with Carl Menger and M.-E.-L. Walras, a co-founder of marginalism and theory of utility. Jevons is the author of the book “The Theory of Political Economy”, 1871, in which he devised the concept of marginal utility, from an additive and separable utility function, although it was not measurable on cardinal terms. These studies were possible thanks to Johann H. von Thünen’s works, who was the first economist to use the word “marginal”, which meaning Jevons adopted in his works using the term “final”. He is also considered as a precursor of Econometrics for his work on business cycle, index numbers and moving averages, topics on which he used his extensive knowledge of mathematics.
Although his works on marginal utility are considered pioneer during the marginal revolution, and important for the development of neoclassical economics, Jevons considered there would be only one possible solution when considering barter exchange. However, there are infinite solutions, as was demonstrated later on by Francis Y. Edgeworth, whose indifference curves are based on Jevons’ earlier work.