His chair in Cornell was filled by Mitchell Feigenbaum, one of the founders of the modern subject of chaos. Kac spent twenty years at Rockefeller University, then decided to spend the rest of his career:
Kanyang upuan sa Cornell ay puno ng Mitchell Feigenbaum, isa sa mga founder ng mga modernong paksa ng ganap na kaguluhan. Kac nagastos dalawampung taon sa Rockefeller University, at pagkatapos ay nagpasya na gastusin ang natitirang bahagi ng kanyang karera: