Lang was a professor at the Yale university for the past 33 years. Before moving to Yale, he was at Columbia for almost fifteen years. Serge Lang was a prolific author. His math publications include about forty math books -- textbooks at various levels and research monographs, and around 150 research papers. Unlike other distinguished mathematicians, Lang was also famous for his forthright views on many different topics, some of which were very controversial. His views on AIDS -- "that a causal link between HIV and AIDS has not been definitively established", for instance. Most of his non mathematical writings are collected in the voluminous book, Challenges, published by Springer. Lang wrote in its introduction:
... parts of this book concern several other cases of questionable academic, scientific, or political behavior, in various combinations. All pieces this book reflect my fundamental interest in the area where the academic or scientific world meets the world of journalism and the world of politics. The pieces deal with various questions of responsibility in all these areas. It turns out that the National Academy of Sciences happens to be involved in all of them in some way or another.
One recurrent problem has been the difficulty I have experienced in getting published. Examples of this difficulty arise throughout. The existing difficulties of getting criticisms of established figures or institutions printed in standard scientific or scholarly journals is one of the fundamental issues dealt with in this book.
Lang never shied away from speaking out. For instance, his article, A Mathematician on the DOD, Government, and Universities, charged that the US Department of Defense regularly use research funding as a means to buy loyalty or to scare and discipline American mathematicians during the Vietnam War. When the American Mathematical Society honored him the Steel Prize in 1999, his response was thus:
I thank the Council of the AMS and the Selection Committee for the Steele Prize, which I accept. It is of course rewarding to find one's works appreciated by people such as those on the Selection Committee. At the same time, I am very uncomfortable with the situation, because I resigned from the AMS in early 1996, after nearly half a century's membership. On the one hand, I am now uncomfortable with spoiling what could have been an unmitigated happy moment, and on the other hand, I do not want this moment to obscure important events which have occurred in the last two to three years, affecting my relationship with the AMS.
Torn in various directions, sadly but firmly, I do not want my accepting the Steele Prize to further obscure the history of my recent dealings with the AMS.
If you visit any reasonable library which also has a math collection, and if you bother to have a quick walk near the math shelves, it's hard not to notice Serge Lang's name. In my first week of M.Sc., I saw so many books by a certain Serge Lang that I thought a group of mathematicians wrote under that name. (A prof had told us about Bourbaki in his very first class!) Lang remained very active till the end, researching, lecturing, writing text books, and publishing research papers. I never met him, but I have heard numerous stories that highlight his humour, his diligence, and of course his eccentricities, from friends, colleagues, and teachers. Very recently, perhaps a few days before his death, he lectured at Berkeley, and my blog friend Vishnu was in the audience. Vishnu wrote in his September 10 post that "it was amazing to see the seventy-eight year old Lang talking with great enthusiasm". Vishnu's post also narrates a cute little incident that shows the lighter side of Serge Lang.
Perhaps no other author has done as much for mathematical exposition at the graduate and research levels, both through timely expositions of developing research topics and through texts with an excellent selection of topics,
Update (September 25): A Gadfly and Mathematical Theorist, a much delayed nytimes obit (link via e-mail from Ravi):
Dr. Lang also threw in a whimsical document, "The Three Laws of Sociodynamics," which states, among other things, that "the power structure does what they want, when they want; then they try to find reasons to justify it."
Dr. Lang started his career as one of the nation's leading thinkers in fundamental mathematics, using aspects of geometry to study the properties of numbers, and evolved into a gifted but challenging teacher.
Decades of students discovered that if they did not pay attention in class, Dr. Lang would throw chalk. "He would rant and rave in front of his students," Dr. Ribet said. "He would say, 'Our two aims are truth and clarity, and to achieve these I will shout in class.' "