

Adam Smith, “The Wealth of Nations”, 1776 was the topic of an earlier blog post.
Ian Stewart, “In Pursuit of the Unknown: 17 Equations that Changed the World“, 2012 also was the topic of an earlier blog post
Wassily Leontif, is a mathematical Economist famous for “Input Output Economics (bookcover BELOW).
BASIC OF INPUT-OUTPUT.
Suppose we have a three (3) sector of a nation. The sectors are “Coal”, “Steel” & “Electric”. The three sectors have input/output numbers from zero (0) to one (1); and the input/output numbers are a “matrix”.
The flow 0.1 is Electric to itself; and, flow 0.2 is Steel to itself. Coal has 0.0 flow to itself (as shown BELOW). All sections summations of input/output is 1.0
Here I presented: Wassily Leontief, “Structure of the World Economy: Outline of a Simple Input-Output Formulation”, NOBEL PRIZE Lecture, 11 December 1973.
SUMMARY.
Leontif Input-Output formulation is essentially tabular as that shown BELOW.
Sector of an economy are: 1, 2, …, Z are used to form the analysis matrix.
This is a typical mathematical economics subject today that is taught in schools. The matrix method is very popular with students, and easy to use in explaining a complex economy.