Guns, Sails and Empires is that rarity among works of history: a short book with a simple, powerful thesis that the entire book is devoted to proving. Carlo Cipolla begins with the question, "Why, after the end of the fifteenth century were the Europeans able not only to force their way through to the distant Spice Islands but also to gain control of all the major sea-routes and to establish overseas empires?" (19) He quickly dismisses motive as a causal factor: motive to circumvent the "Moslem blockade" had existed in earlier centuries as well, but motive without means is empty. Cipolla identifies two developments that provided the means for Europeans to finally succeed beyond their wildest dreams: ships seaworthy enough to reach distant seas; and powerful cannon that could be carried by these ships.