My profession is to be forever journeying, to travel about the universe so that I may know all its conditions. My face is turned toward my father, and my father... from him I have learned all science, he has given me the keys to every kind of knowledge. He has shown me the roads to follow to the extreme confines of the universe, so that since my journey embraces the whole circle of it, it is as if all the horizons of all climes were brought together before me.
— Avicenna/bn Sina, Recital of Hay Ibn Yaqzan