The Roman poet Lucretius, who lived in the first century BC, composed an epic poem, De Rerum Natura (On the Nature of the Universe), whose avowed purpose was to change the way we live our lives, to abandon our fear of the gods and of death, and to see what real happiness is and how to obtain it. The poem explains the atomic nature of the world and our own place in it, examining the microscopic world of atoms and the telescopic world of the universe,...