At the same time that Nicolle was being invited to Mexico to provide his expertise on typhus to the growing international discussion on the disease's contested identity, he was being summoned to return to Paris.The summons was, in part, a sign that Paris was finally giving Nicolle the acclaim he had long sought.Yet, the call came not from the Maison mère, but from the Collège de France. Moreover, the Collège wanted him for the Chair of Experimental Medicine. The position, established a century earlier by François Magendie, had been made still more famous by his student and successor, Claude Bernard, and had continued to be the province of physiology, not bacteriology, right up until 1931. In other words, just as he was attempting to determine the nature of experimentation in microbiology, and the extent to which the laboratory spoke to nature, Nicolle was placing himself in a position to challenge the institutional definition of “experimental medicine” in France. All evidence suggests that he was far more interested in challenging the direction of the IP in Paris. By the end of 1933, he would be well positioned to make that challenge.

The Chair of Experimental Medicine

Nicolle knew he was being considered for the Chair of Experimental Medicine at the Collège de France even before he left for his 1931 mission. Only after his return from Mexico that August, however, did he give the matter serious consideration. Although he was well aware of the position's prestige and had been assured that he “would only have to present myself to be appointed,” he still hesitated, and turned to Duhamel for advice. Marcelle was now settled in Tunis; he was far from finished with his work there. Moreover, he had become quite attached to his adopted home: if he were to take the position, “Would I have to leave Africa?” Duhamel responded emphatically: “no hesitation is possible. You must accept… . I repeat: you must accept.”