Johann Hadji Argyris FRS[1] (Greek: Ιωάννης Χατζι Αργύρης; 19 August 1913 – 2 April 2004) was a Greek pioneer of computer applications in science and engineering,[2] among the creators of the finite element method (FEM), and later Professor at the University of Stuttgart and Director of the Institute of Structural Mechanics and Dynamics in Aerospace Engineering.

[10] His first job was at the Gollnow company in Stettin, where he was involved among other things in high radio transmitter masts.

He created the Aeronautical and Astronautical Campus of the University of Stuttgart as focal point for applications of digital computers and electronics.

Argyris was involved in and developed to a large extent the Finite Element Method along with Ray William Clough and Olgierd Zienkiewicz after an early mathematical pre-working of Richard Courant.

Professor Argyris pioneered in the United Kingdom and Europe computer mechanics and established in the early 1950s the matrix structural theory introducing the first finite elements concepts including effects of material and geometrical nonlinearities.

[13] Argyris died in Stuttgart and is buried in the Sankt Jörgens Cemetery in the city of Varberg, Sweden.