Designated the most Just Princeps This phrase is critical for understanding the position of Gaius in the state. Although Augustus had not formally given him the highest possible power for his expedition in the east, it appears that Gaius was widely perceived as Augustus' successor. Augustus himself wrote him the following letter suggesting as much: the ninth day before the Calends of October (September 23). Greeting Gaius, my dearest little donkey, whom I always miss very much when you are away from me, and my eyes particularly desire to see my Gaius on days such as today, and wherever you have been today, I hope that you have celebrated my sixty-fourth birthday in health and happiness. For, as you see, I have passed the common climacteric of all old men: the sixty-third year. I pray to all the gods, that whatever time is left to me, it may be permitted to me to spend it with both of us safe, and with the Republic in the most favorable condition, with you being a valiant man and succeeding to my station.