In 1898 Bergson became Maitre de conferences at his Alma Mater, L'Ecole Normale Superieure, and was later promoted to a Professorship. The year 1900 saw him installed as Professor at the College de France, where he accepted the Chair of Greek Philosophy in succession to Charles L'Eveque. The College de France, founded in 1530, by Francois I, is less ancient, and until recent years has been less prominent in general repute than the Sorbonne, which traces back its history to the middle of the thirteenth century. Nevertheless, it is one of the intellectual headquarters of France, indeed of the whole world. While the Sorbonne is now the seat of the University of Paris, the College is an independent institution under the control of the Ministre de l'Instruction publique. The lectures given by the very eminent professors who fill its forty-three chairs are free and open to the general public, and are attended mainly by a large number of women students and by the senior students from the University. The largest lecture room in the College was given to Bergson, but this became quite inadequate to accommodate his hearers. At the First International Congress of Philosophy, which was held in Paris, during the first five days of August, 1900, Bergson read a short, but important, paper, Sur les origines psychologiques de notre croyance a la loi de causalite. In 1901 Felix Alcan published in book form a work which had just previously appeared in the Revue de Paris entitled Le Rire, one of the most important of his minor productions. This essay on the meaning of the Comic was based on a lecture which he had given in his early days in the Auvergne. The study of it is essential to an understanding of Bergson's views of life, and its passages dealing with the place of the artistic in life are valuable. In 1901 he was elected to the Academie des Sciences morales et politiques, and became a member of the Institute. In 1903 he contributed to the Revue de metaphysique et de morale a very important essay entitled Introduction a la metaphysique, which is useful as a preface to the study of his three large books. On the death of Gabriel Tarde, the eminent sociologist, in 1904, Bergson succeeded him in the Chair of Modern Philosophy. From the 4th to the 8th of September of that year he was at Geneva attending the Second International Congress of Philosophy, when he lectured on Le Paralogisme psycho-physiologique, or, to quote its new title, Le Cerveau et la Pensee: une illusion philosophique. An illness prevented his visiting Germany to attend the Third Congress held at Heidelberg.