LVII THE DEVELOPMENT OF MATERIAL KNOWLEDGE Throughout the seventeenth and eighteenth centuries and the opening years of the nineteenth century, while these conflicts of the powers and princes were going on in Europe, and the patchwork of the treaty of Westphalia (1648) was changing kaleidoscopically into the patchwork of the treaty of Vienna (1815), and while the sailing ship was spreading European influence throughout the world, a steady growth of knowledge and a general clearing up of men’s ideas about the world in which they lived was in progress in the European and Europeanized world. It went on disconnected from