Astronomer Carl Sagan, the world's most celebrated science writer, Pulitzer Prize winner, and bestselling author, here brings together his last inspirational and provocative collection of essays. Ranging in subject matter from the invention of the game of chess to the question of life on Mars, from global warming to the abortion debate, Billions and Billions is Carl Sagan at his enlightening, entertaining and eclectic best. Applying what we know about science, mathematics and space to everyday life, he also addresses some of today's most controversial issues, providing a beacon of clarity, understanding and unbiased good sense in many difficult areas. In addition, we are given a rare glimpse of Sagan himself in the final essay, 'In the Valley of Shadow', a moving, very personal account of his valiant but ultimately fatal struggle with myelodysplasia, a bone marrow disease. When, in 1994, the National Academy of Sciences awarded Carl Sagan its highest honour, the citation read: 'No one has ever succeeded in conveying the wonder, excitement and joy of science as widely as Carl Sagan and few as well… His ability to capture the imagination of millions and to explain difficult concepts in understandable terms is a magnificent achievement.' Time and again, Sagan has earned that accolade, and in Billions and Billions he demonstrates his incredible ability to cut through the jargon and misinformation to help us make sense of the world around us as it prepares for the challenges of the coming millennium. In the process, he illuminates our ability to understand ourselves and change the world for the better. This is a book that everyone who cares about the future of the world should read.