American mathematician (1928-2015) who made fundamental contributions to game theory, differential geometry, and the study of partial differential equations; he is the only person to be awarded both the Nobel Memorial Prize in Economic Sciences and the Abel Prize. Nash's struggles with paranoid schizophrenia became the basis for Sylvia Nasar's biography, A Beautiful Mind, which was later adapted into an Oscar-winning movie. Ballpoint signature, "John F. Nash, Jr.,” on a white 5 x 3 card. In very fine condition. Encapsulated and graded by PSA/DNA as "NM-MT 8."