Passage: In 1898 Bergson became maître de conférences at his alma mater, École Normale Supérieure, and later in the same year received a promotion to a Professorship. The year 1900 saw him installed as Professor at the Collège de France, where he accepted the Chair of Greek and Roman Philosophy in succession to Charles Lévêque.

Question: What year was he the Prefessor at the College de France?
1900