He was one of the greatest mathematicians of the 20 th century, who devoted his whole life to mathematics. He was Hungarian, born in Budapest and spent much time there, coming back regularly, and having his best friends in (or from) Hungary. We are happy that he was a member of the Editorial Board of our journal. He was a personal friend of many mathematicians all over the world. He is known as the first mathematician who developed the use of probabilistic methods in many other fields of mathematics, first of all in number theory. ErdSs liked and proved the fact that elementary methods can be useful in different fields of mathematics. His best-known contribution was the problem solving and problem posing activity.
The author of this paper met ErdSs' mother earlier than he met ErdSs himself. It happened in 1953, when I was a young mathematician at the Mathematical Institute of the Hungarian Academy where Alfred l~nyi was director. The technical redactor of the Hungarian Acta Mathematicae was ErdSs-n~ni, or Annus n~ni (Aunt Anna). I wrote my first paper and she explained to me how to write a good paper. In the Institute, we knew well who ErdSs was, and it was more than coincidence that R~nyi tried to help ErdSs' mother. (The political situation in Hungary was terrible, e.g., to have a relative in a Western country meant that you were a possible spy!) I and many other colleagues met ErdSs himself for the first time in 1955, in Hungary. He was allowed to enter the country and leave it. He was possibly the only person with a Hungarian passport who had such a "privilege" in those years. As I remember, this permission was organized by his friend Gy. Alexits and supported by R~nyi, P. Tur£n, and Gy. HajSs. We knew that ErdSs had fundamental results in number theory, probability theory, geometry, real and complex analysis, approximation, and interpolation theory.
In 1959 (or 60?), ErdSs visited Moscow. This was his first visit to the country of Joe (Stalin). He stayed there more than one week. R~nyi asked me to help him. In those days, I was a Ph.D. student of Kolmogorov. I met ErdSs every day and tried to arrange his program. First of all, I was to arrange for him to meet Kolmogorov, who was not informed officially that Erd5s was there. When I told him, he said '~¢onderful, he is an ingenious mathematician" and invited him, through me, to meet at the Department of Probability Theory. It was a great event in my life to see them, both great mathematicians, together. They were happy to see each other. They spoke in German, and ErdSs was invited to give a talk to the Moscow Mathematical Society. He agreed and his lecture was organized at the Moscow State University in a huge lecture room auditorium. His lecture was a success. His English was translated by Safarewich, as in those days, only a