Book excerpt: Please note: This is a companion version & not the original book. Sample Book Insights: #1 The miasma theory, which was the prevailing theory in medieval Europe, stated that diseases arose from bad smells. Medieval physicians and scholars believed that diseases were caused by foul airs, and therefore, they would often force local residents to clear away their waste. #2 The disease Rhazes wrote about in the tenth century was similar to chicken pox. He thought that people’s basic constitutions determined whether they suffered from smallpox or measles. #3 The first known disease that afflicted humans was the plague, which was spread by fleas. It was first diagnosed in 1414 in Paris, and was believed to be caused by dying flowers. #4 The Black Death, also known as the Plague of Justinian, was a disease that swept through Europe in the sixth and seventh centuries AD. It was brought to England by the Romans, and it was also known as the Plague of Cadwalader’s Time in Ireland.