The same alternations may be found throughout his life; sometimes, a keen and contemptuous critic, he shows haughty presumption; at other times he descends to the lowest literary platitudes; sometimes he wandered about the delightful suburbs of Dresden lost in the contemplation of nature; at other times he wallowed in prosaic love adventures, from which distinguished friends were obliged to save him, and this while he was elaborating his great work, _Die Welt als Wille und Vorstellung_, which was to astonish the world. “He thus,” remarks Von Sedlitz, “gave the example of a _mania puerperii spiritualis_, such as sometimes takes possession of pregnant women.” Schopenhauer himself told Frauenstedt that at the time when he was writing his great work he must have been very strange in his person and behaviour, as people took him for a madman. One day when he was walking in a conservatory at Dresden, and, while contemplating the plants, talked aloud to himself and gesticulated, an attendant came up and asked him who he was. “If you can tell me who I am,” replied Schopenhauer, “I shall be very much obliged to you.” And he walked away leaving the astonished attendant fully persuaded that he was a lunatic. With such a disposition it is not surprising that Schopenhauer, like many prophets, believed that he was impelled by a demon or spirit. “When my intelligence had touched its apogee, and was, under favourable conditions, at its point of greatest tension, it was capable of embracing anything; it could suddenly bring forth revelations and give birth to chains of thought well worthy of preservation.”[184] In 1816 he wrote: “It happens to me among men as to Jesus of Nazareth when he had to awake his disciples always asleep.” Even in old age he spoke of his great work in such a way as to exclude all doubt as to the inspiration which had produced it, such a work only being possible under the influence of inspiration. At that age he gazed with astonishment at his work, especially at the fourth book, as at a work written by some other person. It is worth while recalling here the doubling of personality so common in men of genius.