Several of Levi's friends and associates have argued otherwise. The Oxford sociologist Diego Gambetta noted that Levi left no suicide note, nor any other indication that he was considering suicide. Documents and testimony suggested that he had plans for both the short- and longer-term at the time. After visiting the apartment complex, Gambetta suggested that Levi lost his balance and fell accidentally, as he had complained to his physician of dizziness in the days before his death. The Nobel laureate Rita Levi-Montalcini, a close friend of Levi, agreed. "As a chemical engineer," she said, "he might have chosen a better way exiting the world than jumping into a narrow stairwell with the risk of remaining paralyzed."