📜 Theorem, law or theory

Farkas' lemma

Lema de Farkas

Date
1902 · confidence high
Place
Cluj-Napoca, Cluj, Romania
Credited to
Gyula Farkas
Field
Knowledge & symbols

What was discovered

A theorem on the solvability of systems of linear inequalities: either the system has a solution or there is a certificate that it has none. Gyula Farkas published it while a professor at Kolozsvár.

Farkas taught at the University of Kolozsvár (now Cluj-Napoca, Romania). The result appeared in the Journal für die reine und angewandte Mathematik in 1902; Fourier had already worked on linear inequalities in 1826.

What it led to

  • duality in linear programming (Dantzig, von Neumann, 1947-1950)
  • Karush–Kuhn–Tucker optimality conditions
  • game theory and mathematical economics

Links

Sources✓ verified 2026-10-09