Tribute to André Lévy-Lang

Caption: André Lévy-Lang and Jean-Pierre Bourguignon at the IHES Board of Directors meeting in May 2012.

It was with immense sadness that I learned of André Lévy-Lang’s passing away on Saturday, August 8. Beyond his extraordinary commitment to building and guiding the Institut Louis Bachelier his great contribution to the academic world, and his many other activities in banking, the press, and preserving the memory of the Shoah, he accompanied the development of IHES with unfailing dedication for more than twenty years.

He had been a member of its Board of Directors since 2004, but his commitment to helping the Institute went back to its first international fundraising campaign in the early 2000s, when he served on the campaign committee chaired by Philippe Lagayette in his capacity as Chairman of the Board. André went on to co-chair, with Andrew Gould, then Chairman and CEO of Schlumberger, the committee for the Institute’s second campaign, the “Fiftieth Anniversary Campaign,” launched in 2008.

His remarkable career brought together science, technology, and the world of finance. After earning a doctorate at Stanford and spending a brief period at the Commissariat à l’énergie atomique, he pursued a career across institutions that combined these three dimensions. This was notably the case at Schlumberger, a remarkable example of a technology company that successfully brought scientific and industrial approaches together over the long term. He spent a dozen years there before entering the world of finance, holding various positions at Paribas from 1974 onward and becoming its Chairman in 1990, a position he held until the bank’s merger with BNP in 1999.

Throughout his life, he retained an undiminished curiosity about science, which naturally led him to become deeply involved in the efforts of an institution such as IHES, fiercely protective of its scientific independence – to strengthen its financial foundations. He brought to the Institute his deep knowledge of the banking world, while also helping it to broaden its connections with the scientific community.

His experience at Schlumberger, combined with the interest of Philippe Lacour-Gayet, then Director of Research, and Andrew Gould, led to the creation of the Schlumberger Chair for Mathematical Sciences at IHES in 2006. The Chair brought a range of new figures into the Institute’s orbit, opening windows onto scientific fields beyond those traditionally represented at IHES. Among the researchers supported by the Chair one finds: at the interface with engineering, Stéphane Mallat, as he completed his transition toward data science before becoming a professor at the Collège de France and also Josselin Garnier and George Papanicolaou, in support of their collaboration on extracting information from stochastic data over time; at the interface between biology and mathematics, Yves Barral, an interaction that continues to this day.

His involvement with IHES also proved instrumental in establishing the Institute’s Japan Fund. Through Yusuke Yasuda, a former colleague at Paribas who had become head of BNP Paribas in Tokyo, André helped open doors that ultimately made the Fund possible.

What struck me whenever I met André was his remarkable ability to listen and his kindness. Unfailingly loyal in attending events of all kinds organised by IHES – he was present at the launch of the fourth fundraising campaign at AXA’s headquarters in December 2025 and at the event held by IHES at the Fondation Louis Vuitton this past June – he was always eager to be kept informed about the substance of the Institute’s scientific choices and always wanted to know more. I imagine that the announcement of Hong Wang’s Fields Medal delighted him as further proof that the Institute had lost none of its ability to take risks and make bold scientific choices.

During my time as Director, André was one of the Board members with whom I most enjoyed talking, both because of the appropriateness of his questions and, of course, the value of his suggestions about new relationships IHES might explore, whether scientific, technological, or financial.

I remember with emotion a very special dinner organized – if my memory is not failing – in 2010 at a restaurant on the Champs-Élysées by former colleagues of André’s at Paribas, perhaps to mark the twentieth anniversary of his becoming Chairman. I was greatly honored to have been invited and to find there people I had met over the years in the United States, Japan, and elsewhere, in an atmosphere filled with the warmth of genuine friendship and admiration for a “superior mind”, a description I came across this morning in one of the tributes paid to him. It seems to me an apt description, provided one immediately adds that André had a gift for putting people at ease. He never talked down to anyone, allowing everyone to benefit from his remarkable ability to listen.

André was indeed a man of exceptional intellectual calibre. When he sat the entrance examination for the École Polytechnique in 1956 as an Egyptian national – he was born in Alexandria – he received the highest marks of all the candidates, forcing the institution to acknowledge that a foreign candidate could rank ahead of the “major”. Determined always to get to the bottom of things, he never missed an opportunity to suggest new avenues to explore, ensuring that no possibility was overlooked.

The world needs more people like André, capable of building genuine bridges between worlds that too often remain apart – I am thinking here of academia, technology, and finance – because they do not sufficiently understand how one another works. This conviction was at the heart of his decision to create the Institut Louis Bachelier at the intersection of these worlds. It was in the same spirit that he developed the Fondation du Risque, at a time when the financial world was struggling to find its bearings amid new and increasingly complex technological possibilities.

It is therefore with a profound sense of gratitude and indebtedness that I extend my deepest condolences to his family and loved ones. I share with them the sadness of losing a great supporter of IHES, who became a personal friend and whose conversations and companionship remain vivid memories in my life.

Jean-Pierre Bourguignon
Nicolaas Kuiper Honorary Professor
Director of IHES from 1994 to 2013