Harvard psychologist and philosopher William James' The Varieties of Religious Experience: A Study in Human Nature explores the nature of religion and, in James' observation, its divorce from science when studied academically. After publication in 1902 it quickly became a canonical text of philosophy and psychology, remaining in print through the entire century. "Scientific theories are organically conditioned just as much as religious emotions are; and if we only knew the facts intimately enough, we should doubtless see 'the liver' determining the dicta of the sturdy atheist as decisively as it does those of the Methodist under conviction anxious about his soul. When it alters in one way the blood that percolates it, we get the Methodist, when in another way, we get the atheist form of mind."

Cuneiform records made some three thousand years ago are the basis for this essay on the ideas of death and the afterlife and the story of the flood which were current among the ancient peoples of the Tigro-Euphrates Valley. With the same careful scholarship shown in his previous volume, The Babylonian Genesis, Heidel interprets the famous Gilgamesh Epic and other related Babylonian and Assyrian documents. He compares them with corresponding portions of the Old Testament in order to determine the inherent historical relationship of Hebrew and Mesopotamian ideas.