When one of my instructors at Berkeley had to take leave due to personal issues, Mihai stepped in as the instructor. The course became one of the most challenging, instructive, and yet enjoyable one during my time at Berkeley. What I will remember about him is the aura of genius that was unmistakable, and the surprising level of warmth and camaraderie he displayed every time he interacted with us. Being as brilliant as he was, I always marveled at his patience when explaining things to his students. This makes me truly sad to a level I have not experience many times in my life.