"Eric Argus has one last chance. His earlier scientific work-- groundbreaking and infamous--jeopardized his reputation and threatened his sanity. But an old university friend hires him at Hansen Research, a Boston laboratory that provides researchers a probationary period of free reign. Argus has a final opportunity to regain his standing and renew his faith in science. He replicates Feynman's double-slit experiment that famously demonstrated the mysterious dual nature of light and matter. Building upon that work, Argus discovers a staggering and elemental difference between humanity and the rest of the animal kingdom: he proves the existence of the human soul"--