"The Tragic Sense of Life," first published in 1912, was the most important philosophical work by Miguel de Unamuno and is now generally considered one of the great existential texts of the 20th century. In the book, Unamuno rejects the life of reason for one of intense passion, faith, and love, establishing Don Quixote as a great role model for the contemporary man.

Miguel de Unamuno (1864-1936) was a profoundly influential Spanish philosopher, novelist, poet, and playwright, recognized for interweaving existential concerns with national identity. His multifaceted body of work bridges literary and philosophical discourses, often addressing themes of individual existence within the context of social and political turmoil. Unamuno served as rector of the University of Salamanca and is heralded as a key figure in the 98 generation, a group of writers who grappled with Spain's moral and cultural crisis at the turn of the 20th century. His seminal work 'Tragic Sense of Life' (1913), epitomizes his philosophical thought, presenting a deep examination of the human struggle for faith and immortality against the backdrop of rational skepticism. This text remains a cornerstone in existential literature, illuminating Unamuno's contemplation of the human condition and spiritual anguish. His distinctive literary style, characterized by introspective prose and a passionate, sometimes agonistic approach to philosophical inquiry, has solidified his standing as an essential voice in early twentieth-century literature and thought.