The work appeared when Schopenhauer was thirty years of age, an extraordinarily early date at which to produce so complete and elaborate a system of philosophy. In this work the outlines of his whole system are permanently fixed. The whole contains, he says, but a single thought. That thought exhibits itself as metaphysics, æsthetics, and ethics. He wrote later many essays and supplements, but these all go towards confirmation and expansion of his earlier work. For the rest of his life he was repeating his original theories, with infinite variation in expression. This is entirely in accord with his own theory of age. At thirty, he maintained, the intellectual and moral endowment has reached its highest development. All that is done later is to vary and expand the main principles already laid down. His book fell still-born from the press. Twenty years later he succeeded in getting his publishers to undertake a second edition, but this too received but scant recognition. Schopenhauer had built great hopes on his work, and his disappointment was bitter when no word of notice greeted its appearance. "I dread silence {27} about my system, as a burnt child dreads the fire," he wrote on one occasion. When bringing his manuscript to the notice of the publisher, he had written that the work "would hereafter be the source of a hundred other books." He confided to a disciple that upon completing the work, he had felt so convinced that he had solved the enigma of the world, that he had thought of having his signet-ring carved with the image of the sphinx throwing herself down the abyss. "My philosophy," he wrote, "is the real solution of the enigma of the world. In this sense it may be called a revelation." Before the book appeared, Schopenhauer travelled to Italy. He first spent some weeks in Venice, where Byron was living at the time. The two, however, did not meet. He then set out for Rome, by way of Bologna and Florence, and there he spent the winter. His time was spent mostly in the art collections, and in the study of Italian. He kept, as he always did in travelling, a diary, recording not so much his observations on things seen, as his moods and moralisings on them.