The story of John Ott's discovery of the role light plays in sustaining physical health is one of the true scientific breakthroughs of the last quarter century. It is the story of an observant, intelligent man who acted upon his observations and then supported them with scientific experimentation. The importance of light has long been known esoterically, but it has largely been ignored by science. Health and Light has led many people to a greater understanding of the subtle role light plays -- both constructively and destructively -- in maintaining physical and emotional health. Health and Light also reveals the rigidity with which established science greets new breakthroughs.