His father, Giovanni, an architect and prominent antifascist, was the brother of the mathematician Rosetta, who was the wife of the writer Ennio Flaiano.

in mathematics from Princeton University in 1953 after completing a senior thesis, titled "On the solubility of linear equations in topological vector spaces", under the supervision of William Feller.

He then pursued graduate studies at Yale University, where he received a Ph.D. in mathematics in 1956 after completing a doctoral dissertation, titled "Extension Theory Of Ordinary Linear Differential Operators", under the supervision of Jacob T.

Beginning in 1966 he was a consultant at Los Alamos National Laboratory, frequently visiting to lecture, discuss, and collaborate, notably with his friend Stanisław Ulam.

Among his many eccentricities, he would not teach without a can of Coca-Cola, and handed out prizes ranging from Hershey bars to pocket knives to students who asked questions in class or did well on tests.