Man is so built that he cannot imagine his own death. This leads to endless invention of religions. While this conviction by no means proves immortality to be a fact, questions generated by it are overwhelmingly important. The nature of life, how ego hooks into the body, the problem of ego itself and why each ego seems to be the center of the universe, the purpose of life, the purpose of the universe — these are paramount questions, Ben; they can never be trivial. Science hasn’t solved them — and who am I to sneer at religions for trying, no matter how unconvincingly to me? Old Mumbo Jumbo may eat me yet; I can’t rule him out because he owns no fancy cathedrals. Nor can I rule out one godstruck boy leading a sex cult in an upholstered attic; he might be the Messiah. The only religious opinion I feel sure of is this: self-awareness is not just a bunch of amino acids bumping together!

Robert A. Heinlein (1907-1988) American writer

Stranger in a Strange Land, Part 4, ch. 33 [Jubal] (1961)
    (Source)

In the "uncut" original version (1960): "Self-aware man is so built that he cannot believe in his own extinction ... and this automatically leads to endless invention of religions. While this involuntary conviction of immortality by no means proves immortality to be a fact, the questions generated by this conviction are overwhelmingly important ... whether we can answer them or not, or prove what answers we suspect. The nature of life, how the ego hooks into the physical body, the problem of the ego itself and why each ego seems to be the center of the universe, the purpose of life, the purpose of the universe -- these are paramount questions Ben; they can never be trivial. Science can't, or hasn't, coped with any of them -- and who am I to sneer at religions for trying to answer them, no matter how unconvincingly to me? Old Mumbo Jumbo may eat me yet; I can't rule Him out because He owns no fancy cathedrals. Nor can I rule out one godstruck boy leading a sex cult in an upholstered attic; he might be the Messiah. The only religious opinion that I feel sure of is this: self-awareness is not just a bunch of amino acids bumping together!"