#### by Lida Barrett

The straightness Andy brings to his mathematics he extends to all that have dealings with him. In these many years together I have never heard a word that seemed false in what he had to say. Nor have I seen him hesitate to take on any task, however onerous, for the welfare of the Department or the University. Needless to say, the rest of us are masters of this art. For, of course, the best way to avoid a chore is to be out of earshot when it is assigned. Hungarians imbibe this principle with their mother’s milk, but Andy, for all his brilliance, never seems to have learned it[3].

Within the profession Andy served in many ways. He was president of the American Mathematical Society in 1981 and 1982. At the Mathematical Association of America he served on the committee on the Putnam Prize Competition (he placed in the top five three years in a row during his years as an undergraduate) and the Science Policy Committee. In 1996 the MAA honored him with its Yueh-Gin Gung and Dr. Charles Y. Hu Award for Distinguished Service [e1].

Andy chaired the committee in charge of the 1986 International Congress of Mathematicians in Berkeley, California. Hope Daly, the staff person from the AMS who handled the operation, says of him, “He was wonderful, a great leader. He quickly understood problems when they arose and had immediate answers. And he was really wonderful to work with, humble, pleasant.” She offers as an example of the many ways in which he could help his action on the morning of the meeting when he saw the staff making direction signs for the somewhat confusing Berkeley campus to replace those the students had taken down the night before. Asking what needed to be done, he was told the signs had to be tacked up. So he took a stack and a hammer and went out and did just that. After the successful congress he edited the proceedings; see [2].

He was a master of exposition for audiences at any level. His 1962 Earle Raymond Hedrick Lectures for the MAA on “The Coordinate Problem” addressed the need for good names. The abstract1 reads:

In the study of mathematical structures, especially when computations are to be made, it is important to have a system for naming all of the elements. Moreover, it is essential that the names be so chosen that the structural relations between the various elements can be expressed by relations between their names. When the structure has cardinal\( \aleph_0 \)it is natural to take integers or finite sequences of integers as names. When the cardinal is\( c \), it is appropriate to take real numbers or sequences of real numbers as names. Most mathematical systems are described initially in terms of purely synthetic ideas with no reference to the real number system. Theorems concerning the existence of analytic representations for different types of structures[are]discussed.

He also wrote for the general reader. In *Science* in 1964 he
explained the relationship between
topology and differential equations
[1].
His first
paragraph sets the tone for that hard task:

It is notoriously difficult to convey the proper impression of the frontiers of mathematics to nonspecialists. Ultimately the difficulty stems from the fact that mathematics is an easier subject than the other sciences. Consequently, many of the important primary problems of the subject — that is, problems which can be understood by an intelligent outsider — have either been solved or carried to a point where an indirect approach is clearly required. The great bulk of pure mathematical research is concerned with secondary, tertiary, or higher-order problems, the very statement of which can hardly be understood until one has mastered a great deal of technical mathematics.

In spite of these formidable difficulties, he concludes his introduction:

I should like to give you a brief look at one of the most famous problems of mathematics, the n-body problem, to sketch how some important problems of topology are related to it, and finally to tell you about two important recent discoveries in topology whose significance is only beginning to be appreciated.

Needless to say, he succeeds.

The other essays in this collection detail the depth and significance of his work in mathematics and mathematics education. Here I have sought to acknowledge how he has contributed both to our profession and far beyond it, to the understanding of the role of mathematics in today’s world.

On a personal note, I found Andy the source of extraordinarily useful nonmathematical information. I have capitalized personally on his knowledge of interesting books, speeches, and other activities nationwide, and the latest scoop on restaurants and auto mechanics in the Cambridge area. It was fun, rewarding, and challenging to work with him. I will miss his presence in the mathematics community.