Between the ability to know and the ability to desire lies the ability to feel, by means of which we feel pleasure or displeasure in some subject matter, approve of it, deem it good, and find it pleasant or disapprove of it, find fault with it, and find it unpleasant. There are thoughts and representations in which we take no part and which are not connected with any sentiments. There are also sentiments that do not pass over into desires. We can find a piece of music, a painting beautiful and be moved by it without desiring anything.

The goal of the ability to know is the true. That is, insofar as we possess a ability to know, we strive to make the concepts in our soul agree with the properties of their objects.

The goal of the ability to feel is the good. That is, insofar as we possess an ability to feel, we strive to make the objective properties agree with our concepts of goodness, order, and beauty. This object is occasionally in us ourselves if we endeavor to alter our thoughts and sentiments themselves in keeping with the rule of goodness, beauty, and so forth.

Thus, within the human being, there are apparently contrasting inclinations to truth and to fiction: to truth as soon as the ability to know is supposed to be engaged, to fiction, on the other hand, as soon as we intend merely to sustain our ability to feel.

In the “Letters on sentiments” [“On sentiments”] I assumed with Monsieur Maupertuis the following nominal definitions: The pleasant sentiment is a representation which we prefer to have than not to have; the unpleasant, on the other hand, a representation which we prefer not to have than to have. In this definition, however, there is a small error that deserves to be noted. For the smallest error in the basic definition of any subject matter can, in subsequent considerations, lead us astray into the most significant misunderstandings. On the basis of the content of the definition, we would have to despise every unpleasant sentiment and wish to see it purged from our soul and destroyed. If we pay attention to ourselves, however, we notice that, in the case of some unpleasant sentiments, our disgust is not always directed at the representation but very often at the object of the representation. We do not always prefer not to have the representation, as required by the definition, but in very many instances merely prefer instead for the object not to be. We disapprove of the evil that has occurred; we wish that it had not happened or that it stood in our power to make things right again. Once, however, the evil has occurred, and if it has occurred without our being in any way responsible for it and without our being able to prevent it, then we are powerfully attracted to the representation of it and long to acquire that representation.

Moses Mendelssohn, one of the most gifted and intriguing figures of the German Enlightenment, first published his Philosophical Writings in 1761, and in a revised edition in 1771. Only one essay (“Rhapsody”) was newly written; the others, dating back to 1754, had already established his reputation as a thoughtful and effective writer on a variety of issues of pressing concern to his contemporaries. In the Philosophical Writings the reader will find: an explanation of the various sorts and sources of pleasure, a nuanced defense of Leibniz's theodicy and conception of freedom, an examination of the ethics of suicide, an account of the “mixed sentiments” so central to the tragic genre, a hypothesis about weakness of will, an elaboration of the main principles and types of art, a definition of sublimity and analysis of its basic forms, and, lastly, a brief tract on probability theory, aimed at rebutting Hume's skepticism.

Despite its rich range of themes, Mendelssohn's collection of six youthful essays does not lack for unity. Their common purpose is to demonstrate the continuing viability of a metaphysical framework shaped by Leibniz and Christian Wolff, especially for a topic – the nature and variety of sentiments – often neglected by that metaphysical tradition and treated with greater sensitivity by English and French authors. “Sentiment” stands here for an emotionally and hedonically charged human knowledge or awareness by way of the senses, one that can be “perfect or complete” when its object is something beautiful.

The words “enlightenment,” “culture,” “education” are still newcomers to our language. At the present time they belong merely to the language of books. The common masses scarcely understand them. Should this be a proof that the theme is also novel to us? I do not believe so. One says of a certain people that they do not have a definite word for virtue or for superstition, although one may correctly ascribe a considerable measure of both to them.

Linguistic usage, meanwhile, appears to want to make a distinction among these words which have similar meanings, but it has not yet had time to establish their borders. Education, culture, and enlightenment are modifications of social life, effects of the hard work and efforts of human beings to improve their social condition.

The more that art and hard work have brought the social condition of a people into harmony with the vocation of a human being, the more educated this people is.

Education breaks down into culture and enlightenment. The former seems to apply more to the practical dimension, that means – objectively – to excellence, finesse, and beauty in trades, arts, and society's mores, and – subjectively – to proficiency, hard work, and skill at those trades, arts, and mores as well as to inclinations, drives, and habits making up that proficiency, hard work, and skill.

Theocles, an English philosopher who inherited the name of that dear enthusiast known to us from the Earl of Shaftesbury's The Moralists, had left his homeland some time ago. The mixture of seductive imagination and French frivolity, peddled as metaphysics by so many of his countrymen, was so starkly at odds with his proclivity for rigor and fundamentals that he made the decision to renounce his fatherland, his tranquility, and his friends' embrace in order to search for a people that treasures accurate thinking more than free thinking. Germany seemed to him to hold out the promise of such a people. He read the immortal writings with which our countrymen have enriched the learned world in the past century, and people say that the soberness, indeed, the very dullness for which they are reproached by some petty critics, was one of the things that drove him to become acquainted with this nation. He went from school to school, and, in the guise of a curious soul simply passing through, he had the pleasure of attending all the gatherings of learned societies anonymously. He is supposed to have been more than a little astonished, however, by the specious and careless manner of our present philosophers. He apparently wrote his friends back in England that his hopes were betrayed and that even in Germany the philosophical dilettante had gotten the upper hand.

Introduction

The criticism is commonly advanced against philosophy that, in its doctrines, no particular conviction is ever to be hoped for since in every century new systems rise up and glimmer for a while only to pass away in turn. In our days the poems, the speeches, the historical and critical writings, the statues, and other artworks of the ancients are still admired as masterpieces, and, to a degree, more is to be gained from the study of them than from the study of nature itself. In philosophy, however, the words of the past have become almost useless in the present day. To be sure, the most famous systems still contain some useful materials, but, as is commonly believed, they are not worth the trouble of searching through the ruins and digging up the rubble that covers them. It is inferred from this that taste or the sentiment of beauty and order is far more durable and reliable than reason or convictions about philosophical truths. For taste has preserved itself in much the same way since Homer while reason changes its shape with every age of humanity, and, hence, the former must be more certain and less subject to doubt than the latter.