José Ortega y Gasset was a Spanish philosopher and essayist, born on May 9, 1883, in Madrid. He is best known for his work in existentialism and his influential ideas on the nature of human existence. Ortega's most famous book, The Revolt of the Masses, critiques the rise of mass society and emphasizes the importance of individualism and personal responsibility. Ortega studied at the University of Madrid and later in Germany, where he was influenced by philosophers like Friedrich Nietzsche and Henri Bergson. Throughout his career, he contributed to various fields, including sociology, politics, and education, and he played a significant role in the cultural life of Spain until his death on October 18, 1955.