In Chapter 3, Diamond discusses many aspects of Spanish society that allowed the Spanish to conquer the Inca rather than the Inca conquering the Spanish. These include:
- Weapons. Diamond discusses the way in which the Spaniards' weapons helped them defeat the Inca. The steel swords, daggers, lances, and armor and the guns were all aspects of the Spanish society that allowed them to defeat the Inca.
- Ships. The Spanish had ships capable of crossing the ocean. The Inca did not.
- Political organization. Diamond says Spain's centralized political organization allowed it to finance the ships and to pay people to sail them.
- Writing. The ability to store knowledge in written form and to transmit that knowledge (as well as things like orders) to others via writing helped make the Spanish capable of undertaking such conquests. It also helped motivate them to conquer because written materials caused Spaniards of Pizarro's time to know about the treasure held by Indian societies like the Aztecs.