The fame of these great thinkers and writers in philosophy and in medicine came to be known not only through the distribution of their books long after their death, but during their lifetime, and in immediately subsequent generations, ardent seekers after knowledge, who were themselves afterwards to become famous by their teaching and writing, found their way into the Arabian dominions in order to take advantage of the educational opportunities afforded. These were better than they could secure at home in Christian countries, because the process of bringing culture and devotion to literature and science into the minds of the Northern nations, who had replaced the old Romans in Europe, was not yet completed. Bagdad and Cordova were the two favorite places of educational pilgrimage. The names that are most familiar among the scholars in the Middle Ages in Europe are those of whom it is recorded that they made long journeys in order to get in touch with what the Arabs had preserved of the old Greek civilization and culture. Among them are such men as Michael Scot or Scotus, Matthew Platearius, who was afterwards a great teacher at Salerno; Daniel Morley, Adelard of Bath, Egidius, otherwise known as Gilles de Corbeil; Romoaldus, Gerbert of Auvergne, who later became Pope under the name of Sylvester II; Gerard of Cremona, and the best known of them all, at least in medicine, Constantine Africanus, whose wanderings, however, were probably not limited to Arabian lands, but who seems also to have been in Hindustan. We are rather prone to think that this great spirit of going far afield for knowledge's sake is recent, or, at least, quite modern. As a matter of fact, one finds it everywhere in history. Long before Herodotus did his wanderings there were many visitors who went to Egypt, and many more later who went to Crete, and many more a few centuries later who went to the shores of Asia Minor seeking for the precious pearl of knowledge, and sometimes finding it without finding the even more precious pearl of wisdom, "whose worth is from the farthest coasts."