Being and Time Heidegger's "description of the world of phenomena" to be "fascinating, but maddeningly abstract". He suggests that much of "Being and Time" is a "description of a private spiritual journey" rather than genuine philosophy, and notes that Heidegger's assertions are unsupported by argument. Stephen Houlgate compares Heidegger's achievements in "Being and Time" to those of Kant in the "Critique of Pure Reason" (1781) and Hegel in "The Phenomenology of Spirit" (1807) and "Science of Logic" (1812-1816). Simon Critchley calls the work Heidegger's "magnum opus", and writes that it is impossible to understand developments in continental philosophy after Heidegger without understanding it.
Philosophy and literature 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