In The Touchstone of Life, eminent biophysicist Werner Loewenstein seeks answers to ancient riddles by applying information theory to recent discoveries in molecular biology. Taking us into a microscopic world, he lays bare an all-pervading communication network inside and between our cells - a web of extraordinary beauty, where molecular information flows in gracefully interlaced circles. Loewenstein then takes us on a journey along that web and we meet the macromolecules, and see how they capture information from their surrounds.