After 1818, when The World as Will and Idea appeared, he published nothing further until 1836. In that year, a small book called On the Will in Nature appeared. It was described on the title-page as "a discussion of the corroborations which the philosophy of the author has, since its first appearance, received at the hands of empirical science." During these eighteen years, in which no new work of his was published, he had been collecting from all that he read, or saw, or heard, everything that could in any way be brought to bear as evidence towards the proof of his main theories and principles. Especially had he been on the alert with regard to scientific investigation, believing that his own sceptical generation would be most strongly influenced by anything that science could bring forward as confirmation of his metaphysical principles. Physics, he thought, had arrived at the point where it touches metaphysics. He was now confident that the time for his philosophy was ripening. But in spite of this confidence, the book met with no more recognition than had his previous works.
In 1838 he competed successfully for a prize offered by the Scientific Society of Drontheim, in Norway, for the best essay on the question "whether free-will could be proved from the evidence of consciousness." The subject could not have been more happily chosen to suit him. His essay won the prize, and he was elected a member of the Society. He obtained permission from the Society to publish his essay in Germany.
Meanwhile he was competing for another prize, offered by the Royal Danish Academy of the Sciences, at Copenhagen, on the subject of the sources or the basis of morality. He was confident of success, and wrote to the Academy asking that the award might be speedily made public, as he proposed to publish his essay along with the one which had been successful in Norway. His confidence was premature, for when the Danish Academy made known its decision, it announced that Schopenhauer's essay was the only one sent in, but that it was unworthy of the prize on several grounds, one of which was, that several of the chief philosophers had been treated with contempt.
From this time his rage against the three philosophers, Hegel, Fichte, and Schelling, knows no bounds. He attributed his failure to win recognition to a conspiracy among them and their followers. His writings abound in violent invective against them. In several ways there are points of contact between the system of Schopenhauer and that of Hegel, but Schopenhauer refused to admit any kinship between them.
His two treatises were published together, as he had intended. They appeared in 1841 as The Two Fundamental Problems of Ethics. These two problems are the freedom of the will and the basis of morality. The treatment is little more than an expansion of the theories set forth in his chief work. He finds the roots of morality in sympathy. The sense of brotherhood, which binds together individual and individual, and welds them into an organic whole, is the foundation on which all the moral sentiments are built. All goodness, love, virtue, and nobility of character spring from the same source, from sympathy, which is the same in its nature as pure love. Beyond the egoism, which is fostered by the world around us, there exists also the principle of altruism, impelling men to self-sacrifice, unselfishness, and devotion.
The second edition of The World as Will and Idea, which appeared in 1844, seemed at first as likely to fail of attaining recognition as the earlier one. But a change was now at hand. The reign of optimistic pantheism was approaching its end in Germany. The lofty idealism, which was the strength of the dominant school of thought, and which found political expression in the revolutionary movements of 1848, was now followed by a wave of reaction. The democratic movement, after obtaining some temporary triumphs, was checked completely for the time, and a wave of weariness and discouragement passed over the country. Schopenhauer looked on, while Frankfurt was torn violently asunder in the throes of its revolution. His sentiments were against the democratic party, and he seems to have feared, above all else, the possibility of losing his private means. In letters written at this time to his friends, Schopenhauer expresses his dislike and disapproval of the great national movement of 1848. He was a thorough-going individualist, and the movement, which stirred to the depths the finest natures of the time, found no response in Schopenhauer's heart. His room was used by Austrian soldiers, who shot from the windows upon the democrats below.
His political views are expressed again in his will, made in 1852, in which Schopenhauer left the greater part of his estate to be spent for the benefit of the soldiers who had been wounded at Berlin, in 1818, in defence of the royal party against the democratic revolutionaries. In his view, the State exists only to secure safety of persons and property. It is a strange error, he says, to attribute to the State any moral function. It is to be regarded merely as the night-watchman, who protects us from thieves and robbers.
The German Parliament, which sat at Frankfurt, had but a short-lived existence. In the reaction which followed, Schopenhauer's philosophy found an open door. Disciples attached themselves gradually to the philosopher, and by degrees his system gained ground at home and abroad.
The work which won for him more popularity than any other, was Parerga and Paralipomena (Chips and Scraps), published in 1851. The work had been declined by three publishers before a Berlin firm agreed to publish, without any payment to the author. The book consists of essays of a very heterogeneous kind, and of varying length. Most of the chief problems discussed in his larger works are treated again in the essays. Religion, education, archæology, Sanscrit, style, noise, ghosts, and immortality are a few of the subjects dealt with. Schopenhauer's reading was wide. His quotations range freely over oriental, classical, and modern literature.
The success which followed the publication of this book was reflected on the earlier works, and it was now possible to bring out further editions. Schopenhauer's delight at this tardy recognition was unbounded. Every scrap of applause was gathered and absorbed with eagerness. In his letters during this period, everyone who differs from him is denounced as a charlatan and a windbag. Everyone who says anything at all similar is attacked as a plagiarist. Every adversary is moved by the meanest motives. So virulent is his abuse, and so coarse his language, that words in his letters have sometimes to be changed for an initial. Nothing short of adulation, could satisfy his hungry vanity. Even when the universities at last acknowledged him, and offered a prize for the best exposition and criticism of his system, he was enraged at the award of the prize to a student who treated him as of more importance in a literary than in a philosophical capacity. Praise of any other philosophy than his own filled him with bitterness. His correspondence with Frauenstadt, Lindner, and Asher is full of such weakness. It may be doubted whether any great man ever left behind him letters of so trifling a nature, so steeped in vanity and so resentful of any breath of criticism.