Physicist Jerome Elbert writes that souls cannot exist, because “if souls exist and are essential for thinking and decision making, our mental processes involve frequent communications from the brain to the soul and from the soul to the brain.” As a scientist, Elbert confesses, “I find the idea of such interactions very disturbing.” The reason he is troubled is that he cannot possibly see how an immaterial entity like the soul can move or influence a material object like the brain. He also raises a deeper issue. “If such interactions exist, the human brain is an interface to another, nonphysical world. Such inter- actions suggest that the rules of science apply to all of the universe— except for human beings…. This picture gives humans a unique position in the universe. This anthropocentric picture seems very unacceptable to the scientific worldview.” For Elbert, the existence of the soul jeopardizes the very nature of modern science.