He obtained his high school certification from the Liceo-Ginnasio Giambattista Vico in Naples in classical subjects, although he showed a stronger aptitude for mathematics and physics.

He was drafted in March 1943 but nevertheless managed to take examinations during the summer before joining the resistance movement against the Germans in the defence of Rome in September.

In the 1945–1946 academic year he declined a specialization at the Scuola Normale in the Faculty of Sciences in favour of an assistant position at the Istituto Universitario Navale.

It was about this time that his research efforts shifted toward the emerging field of variational inequalities, which he modelled after boundary value problems for partial differential equations.

[1][4] He was also director of the Istituto per le Applicazioni del Calcolo of Consiglio Nazionale delle Ricerche from December 1968[5] to 1974.