Sex, Ecology, Spirituality: The Spirit of Evolution is a 1995 book by integral philosopher Ken Wilber. Wilber intended it to be the first volume of a series called The Kosmos Trilogy, but subsequent volumes were never produced. The German edition of Sex, Ecology, Spirituality was entitled Eros, Kosmos, Logos: Eine Jahrtausend-Vision ("A Millennium-vision"). The book has been both highly acclaimed by some authors and harshly criticized by others.