Eccentric 19th Century Danish Philosopher Soren Kierkegaard has dramatically impacted 20th Century thought in philosophy, religion, theology, ecclessiology, psychology, and many other fields. Either/OR, Kierkegaard believed, was "the beginning" of his authorship, though he had published two earlier works, one on Hans Christian Anderson and another called The Concept of Irony both of which betray Kierkegaard's deep interest in literature.
Written under the pseudonym Victor Eremita the 2 volumes of Either/OR are the writings of a "young man" (Vol. I) and records the ethical journey of the young man in his life, and particularly in romance. The "young man" is ironic and his writings reflect the ethical realities of dialectical existance. This culminates in the literary and philisophical masterpiece (one chapter in this book) known as the Seducer's Diary.
Either/OR is considered to be one of, if not arguably the seminal work produced by Kierkegaard. It certainly ranks in importantce with Fear and Trembling, and Concluding Unscientific Post-Script in its influence. For those who are interested in philosophy, literature, psychology, or religion, Kierkegaard is required reading.