In many ways, "I and Thou" is regarded as a classic. The book is a very profound proposition about how to approach our existence in the world. Relationships are a major theme in the book, as they provide meaning to human existence. Buber says that at the end of the day, every relationship leads us to God, who is the Eternal Thou. The most recent translation of the original book has a lot of footnotes that explain where the previous version got things wrong or was unclear. Additionally, professor Walter Kaufmann, who retranslated "I and Thou," wrote an extensive prologue that shed new light on the book and on Buber's philosophy.