Ordinary Europeans are worrying about their uninvited guests.

French President Emmanuel Macron and German Chancellor Angela Merkel opened the global Frankfurt Book Fair last week, preaching European unity and cultural diversity to thousands of book buyers, agents, editors, and publishers. But French author Michel Houellebecq’s appearance and reading from Submission stole the show.

“There are so many groups trying to spread hatred, fanaticism, and dogmatism, and we have to stand up to that,” Macron declared to the crowd, leaving what groups he was thinking of unnamed. Books are “what holds us together, what prevents us from closing ourselves off, and prevents us from giving way to fear, brutality, and disunity.” They “help us to understand and see what we have in common, and to understand our differences,” Merkel added with signature vacancy. “In literature, we see the reflection of the soul of our society, which is based on freedom, and that freedom of expression goes hand-in-glove with political freedom.”