The basic premise of The Denial of Death is that human civilization is ultimately an elaborate, symbolic defense mechanism against the knowledge of our mortality, which in turn acts as the emotional and intellectual response to our basic survival mechanism. Becker argues that a basic duality in human life exists between the physical world of objects and a symbolic world of human meaning. Thus, since man has a dualistic nature consisting of a physical self and a symbolic self, man is able to transcend the dilemma of mortality through heroism, a concept involving his symbolic half. By embarking on what Becker refers to as an "immortality project" (or causa sui), in which he creates or becomes part of something which he feels will last forever, man feels he has "become" heroic and, henceforth, part of something eternal; something that will never die, compared to his physical body that will die one day. This, in turn, gives man the feeling that his life has meaning; a purpose; significance in the grand scheme of things. The Denial of Death is a work of psychology and philosophy written by Ernest Becker and published in 1973. It was awarded the Pulitzer prize for general non-fiction in 1974, two months after the author's death. The book builds largely on the works of Søren Kierkegaard, Sigmund Freud, and one of Freud's colleagues, Otto Rank.