Abstract
This article is of both a historical and philosophical nature. It aims to present the intellectual relationship between the Spanish philosopher José Ortega y Gasset and one of the most influential German thinkers of the first half of the twentieth century, Nicolai Hartmann. It is based on hitherto unknown and unpublished correspondence that the philosophers conducted intermittently between 1907 and 1912. The correspondence was found in the archives of the José Ortega y Gasset – Gregorio Marañón Foundation in Madrid along with other letters that show the relationship between the Spanish author and representatives of the neo-Kantian Marburg School, including its founder Hermann Cohen, as well as Paul Natorp, Ernst Cassirer, and Heinz Heimsoeth.