Adorno's 100th anniversary is more difficult to celebrate than the anniversaries of other thinkers. In the early days there was a collective enterprise of thinking with Horkheimer, who in 1930 became the director of the "Institute for Social Research" in Frankfurt. Sometimes the "twin thinkers' were compared to Marx and Engels to whom both owed a lot. In the tradition of Hegel both wanted to overcome the division of philosophy and empirical research in a critical philosophy of history.