Other philosophers have resorted to narrative to get their teachings across. The classical 12th century Islamic philosopher, Abubacer (Ibn Tufail), wrote a fictional Arabic narrative "Philosophus Autodidactus" as a response to al-Ghazali's "The Incoherence of the Philosophers", and then the 13th century Islamic theologian-philosopher Ibn al-Nafis also wrote a fictional narrative "Theologus Autodidactus" as a response to Abubacer's "Philosophus Autodidactus". The German philosopher Friedrich Nietzsche often articulated his ideas in literary modes, most notably in "Thus Spoke Zarathustra", a re-imagined account of the teachings of Zoroaster. Marquis de Sade and Ayn Rand wrote novels in which characters served as mouthpieces for philosophical positions, and act in accordance with them in the plot. George Santayana was also a philosopher who wrote novels and poetry; the relationship between Santayana's characters and his beliefs is more complex. The existentialists include among their numbers important French authors who used fiction to convey their philosophical views; these include Jean-Paul Sartre's novel "Nausea" and play "No Exit", and Albert Camus's "The Stranger". Maurice Blanchot's entire fictional production, whose titles include "The Step Not Beyond", "The madness of the Day", and "The Writing of Disaster", among others, constitutes an indispensable corpus for the treatment of the relationship between philosophy and literature. So does Jacques Derrida's "".