According to Schubert's theory, man originally had the power of working miracles. Sin bereft him of his power over nature, and after this there was always something dark and dæmonic connected with the miracle-working gift--with the oracles of Greece, for instance, and with all heathen sorcery. The old, natural miraculous power was revived in Christ. In its dæmonic form it has reappeared among the Rosicrucians and the Freemasons (the secret societies which played so important a part in the imagination of Schubert's day); and it is also observable in such phenomena as animal magnetism, clairvoyance, &c. Adam Müller writes: "Schubert's book seems to me the best which the 'Naturphilosophie' has produced; its author, though not superior to Schelling in polemical and critical talent, is certainly his superior in feeling, in sincerity, and above all in erudition.... In Schubert's writings I find a glorified, yet in all essentials accurate presentment of an earlier stage of my development, when my one longing was, that all that was human and personal in my power of achievement might, as it were, dissolve into the smoke of a sweet incense, an offering to the God I worshipped. How I longed to be able to divest myself of name and personality, and become the most devoted of martyrs or the most priestly of priests" (der geistlichste Geistliche). Every one read the book, and even a mind like Kleist's allowed itself, as we have seen, to be engrossed by all this pretentious foolishness. Mysticism was the order of the day, and it is curious to see how the mystic element, the strange trinity of sensuality, religion, and cruelty, insinuates itself into all Kleist's dramas. Take, for example, that remarkable tragedy, _Penthesilea_. The heroine is the wild queen of the Amazons, who is waging a victorious war upon both the Greeks and the Trojans. It is a law among the Amazons that each must capture in battle the man who is to be her husband; then, when the war is over, she lives with him in peace and happiness. Penthesilea has conceived quite as fatal a passion for Achilles as Käthchen's for Count Strahl. But in Penthesilea love shows itself in a different way; it takes the form of cruelty. In every battle she pursues Achilles, thirsting for his blood. If Käthchen loved like a dog, Penthesilea loves like a tigress escaped from a Bacchanalian procession. It is plain that it is his own temperament with which Kleist has endowed the Amazon queen. She cares for nothing, will take nothing, but Achilles, just as he refused to aim at anything, to be content with anything, but the highest place of honour. Her wild haste to conquer her beloved corresponds with his desire to attain his aim at one blow, with his drama, _Robert Guiscard_. Like Kleist, she can only live when she is striving after what her soul desires. She says, what her author might have said:[6] "I should go mad if I did not attempt all that is within the bounds of possibility."