Risk management is the element for successful business operation, stock investment, financial insurance and so on, and also changes the human nature of gamble liking into the power of increasing economy, improving living standard and boosting scientific and technological development. This book researches the hard progress of human beings exploration risks. There are always two thoughts existing, one is insisting that the best decision should be based on the past models and statistics; the other deems that the best decision should depend on the subjective judgment according to the uncertain future. From ancient Greek, ancient Roma and Renaissance to nowadays, the author illustrates complicated investment ideas in the way of refreshing stories, describing how philosophers, mathematicians, scientists, thinkers and businessmen endeavored to make use of future to service now. Risk is a choice more than a fate, which depends on the free degree of our choosing.