Heinrich Heine, in a book still very much worth reading, entitled "On the History of Religion and Philosophy in Germany" (Zur Geschichte der Religion und Philosophie in Deutschland), imagines Kant's faithful old servant Lampe, umbrella under arm, watching sadly his master's merciless destruction of all the ancient certainties; and "then Immanuel Kant has mercy upon him and shows that he is not only a great philosopher but also a good man; he considers the matter and says to himself, half good-naturedly, half ironically: "Old Lampe needs a God, otherwise the poor man cannot be happy; man, however, should be happy on earth, as is taught by Practical Reason; for all I care, well then, may Practical Reason guarantee the existence of God". Consequently, Kant sets out to distinguish between Theoretical Reason and Practical Reason, and with the latter, as if with a magic wand, he called back to life again the corpse of Deism killed by Theoretical Reason."^*280