Aetius, or Aetios, to use for the nonce the Greek spelling of his name, which sometimes occurs in medical literature, and should be known, has been the subject of very varied estimation at different times. About the time of the Renaissance he was one of the first of the early writers on medicine accorded the honor of printing, and then was reprinted many times, so that his estimation was very high. With the reawakening of clinical medicine in the seventeenth century his reputation waxed again, and Boerhaave declared that the works of Aetius had as much importance for physicians as had the Pandects of Justinian for lawyers. This high estimation had survived almost from the time of the Renaissance, when Cornelius went so far as to say: "Believe me, that whoever is deeply desirous of studying things medical, if he would have the whole of Galen abbreviated and the whole of Oribasius extended, and the whole of Paulus (of AEgina) amplified, if he would have all the special remedies of the old physicians as well in pharmacy as in surgery boiled down to a summa for all affections, he will find it in Aetius." Naturally enough, this exaggerated estimation was followed by a reaction, in which Aetius came to be valued at much less than he deserved. After all is taken into account in the vicissitudes of his fame, it is clear, however, that he is one of the most important links in the chain of medical tradition, and himself worthy to be classed among makers of medicine for his personal observations and efforts to pass on the teachings of the old to succeeding generations. ALEXANDER OF TRALLES An even more striking example than the life and work of Aetius as evidence for the encouragement and patronage of medicine in early Christian times, is to be found in the career of Alexander of Tralles, whose writings have been the subject of most careful attention in the Renaissance period and in our own, and who must be considered one of the great independent thinkers in medicine. While it is usually assumed that whatever there was of medical writing during the Middle Ages was mere copying and compilation, here at least is a man who could not only judiciously select, but who could critically estimate the value of medical opinions and procedure, and weighing them by his own experience and observation, turn out work that was valuable for all succeeding generations. The modern German school of medical historians have agreed in declaring him an independent thinker and physician, who represents a distinct link in medical tradition.