The written version of the citations that were read at the memorial session at the recent CT06 conference: ********************************************************************** UNIVERSITY of PENNSYLVANIA Citation accompanying the honorary degree of Doctor of Science conferred on May 22, 1977 SAUNDERS MAC LANE Following in the footsteps of Rene Descartes, Saunders Mac Lane has shown that disparate parts of mathematics are categorically the same. Establishing himself as a master of several specialties, he went on to reach for universal solutions. In an age when mathematics has led to increasingly complex resolutions, he has chosen to study the similarities. By developing what seemed to some a nonsensical abstraction for generalizing difficulties, he achieved a method for unifying mathematics. Through his insistence that the triple of algebra, analysis, and geometry are one, he has accomplished his object -- the transformation of the map of mathematics. As Max Mason Distinguished Service Professor of Mathematics at the University of Chicago, past president of the American Mathematics Society, and current Vice President of the national Academy of Sciences, Saunders Mac Lane has given distinguished service to the community of American Scientists. Young mathematicians throughout the world, in deriving extensions of his work, have recognized its truly global dimension. With the knowledge that, in Saunders Mac lane, the scholar and the gentleman are naturally equivalent, and with particular gratitude for his role in bringing excellence in mathematics to this university, the Trustees are pleased to award a former colleague and Associate Trustee the honorary degree, Doctor of Science. ********************************************************************** UNIVERSITY of PENNSYLVANIA Citation accompanying the honorary degree of Doctor of Science conferred on May 20, 1985 SAMUEL EILENBERG Arriving in this country, a prodigy from Warsaw, when American mathematics was but a kernel of its present image, you have nurtured its growth over the years, and, in the process, naturally transformed yourself into the most international as wall as the most American of mathematicians. A master theoretician of geometry, algebra, automata, and formal languages -- our greatest mathematical stylist -- you defined the very categories of modern mathematics. By mastering those categories you enriched them, and by enriching them you laid the foundations for what now is commonplace. When others were content to wrestle with the complex, you created categories for the complex; when others ignored the degeneracies, you faced them, when others found only obstructions you founded the theory of obstructions. You created the exact tools to classify the spaces of mathematics and the the space in which to classify them. Your singular constructions became the standard. Your style became _the_ style. Expert in collecting Indonesian bronzes, and poker chips, while eschewing formal honors, you have nonetheless garnered acclaim as University Professor of Mathematics at Columbia University -- and card-carrying member of the Society of Bourbaki. Aware that your truest honor is the esteem in which are are held by your students, including your colleagues at the University of Pennsylvania, the Trustees prevail upon you, Samuel Eilenberg, to accept from their hand the formal proof of their admiration, the honorary degree, Doctor of Science