THE Trocadero was not a part of Paris lined with cafes. It remains however an area in the French capital that is teeming with people. Its strategic location offers beautiful views, and is considered by many to be the best spot to view the Eiffel Tower.

On a day in the year 1970, at a caf facing the park that leads to the Eiffel Tower, three young French researchers met. Pierre Labrousse, Christian Pelras, and Denys Lombard had not known each oth