In the Middle Ages, while Europe was mired in superstition and feudal chaos, Baghdad was the intellectual center of the world. It was there that an army of translators and scholars took the wisdom of the Greeks and combined it with their own cultural traditions to create a scientific, mathematical and philosophical golden age. Their accomplishments were staggering, including the development of modern medicine, chemistry, and algebra. Muslim scientists correctly calculated the circumference of the globe in the tenth century. Muslim musicians introduced the guitar and musical notation to Europe. And Muslim philosophers invented the scientific method and paved the way for the Enlightenment.