We live a miracle everyday, a world of coloured reflections in a river, scents of flowers, birdsong, a warm breeze. Buried below our living experience, science has discovered a world of atoms and vibrations, a world of blind elementary forces. These forces operate everywhere in the known universe, including the chemistry of our bodies. Most poignantly they operate in our brains. How does the miracle of our conscious life emerge from this dry world of atomic forces? Should we expect science to give a satisfactory answer to this question? Practical developments such as genetic engineering and brain imaging have brought a contemporary vitality to these questions. The book explores the linked hierarchy of science, from physics to brain structure. Within this journey, progressively deeper questions are asked about the nature and limits of scientific explanation.