Art. Abstract metaphysical term. Men began by collecting observations on the nature, function, use and qualities of beings and their symbols. Then they gave the name of science or art to the center or focal point to which they linked the observations they had made, in order to create a system of instruments, or of rules which were all directed toward the same object. That is the most general meaning of art. To give an example: Men reflected on the usage and function of words and subsequently invented the word "grammar." Grammar is the name of a system of instruments and rules that relate to a specific object; this object is articulated sound. The same is true of the other arts and sciences. See Abstraction.

 
Origin of the arts and sciences . In pursuit of his needs, luxury, amusement, satisfaction of curiosity, or other objectives, man applied his industriousness to the products of nature and thus created the arts and sciences. The focal points of our different reflections have been called "science" or "art" according to the nature of their "formal" objects, to use the language of logic. See Object. If the object leads to action, we give the name of "art" to the compendium of the rules governing its use and to their technical order. If the object is merely contemplated under different aspects, the compendium and technical order of the observations concerning this object are called "science." Thus metaphysics is a science and ethics is an art. The same is true of theology and pyrotechnics.

 
Speculative and practical aspects of an art . From the preceding it is evident that every art has its speculative and its practical aspect: the former consists in knowing the principles of an art, without their being applied, the latter in their habitual and unthinking application. It is difficult if not impossible to go far in the practice of an art without speculation, and, conversely, to have a thorough knowledge of the speculative aspects of an art without being versed in its practice. In every art there are many particulars concerning its material, its instruments, and its application which can only be learned through practice. It is the function of practice to present difficulties and phenomena, while speculation must explain the phenomena and solve the difficulties. Consequently, only an artist who can think logically can talk well about his art.

 
Division of the arts into liberal and mechanical arts . When men examined the products of the arts, they realized that some were primarily created by the mind, others by the hands. This is part of the cause for the pre-eminence that some arts have been accorded over others, and of the distinction between liberal and mechanical arts. This distinction, although it is quite justified, has led to bad consequences because it has given a low name to people who are very worthy and useful, and encouraged us in a certain natural laziness. We are all too inclined to believe that it is beneath the dignity of the human spirit to apply oneself diligently and continuously to specific and concrete experiments and objects, and that our mind forfeits its dignity when it descends to the study, let alone the practice, of the mechanical arts; the mind here stoops to questions in which research is laborious, reflection inglorious, and exposition difficult; such questions are dishonorable to deal with, countless in number, and of scarcely any value. Minui majestatem mentis humanae, si in experimentis et rebus particularibus, etc. (Bacon, Novum Organum ). [2] This prejudice has tended to fill the cities with useless spectators and with proud men engaged in idle speculation, and the countryside with petty tyrants who are ignorant, lazy, and disdainful. Such was not the thinking of Bacon, one of the foremost geniuses of England, nor of Colbert, one of the greatest ministers of France, nor, in a word, of the right-thinking and sensible men of all times. Bacon considered the history of the mechanical arts the most important branch of true philosophy; therefore he certainly did not scorn its practice. Colbert considered the industry of the people and the founding of manufactures the most reliable resource of a kingdom. In the opinion of those who today can discern true worth, the state benefited no less from a man who filled France with engravers, painters, sculptors, and artists of all types, who wrested from the English the secret of the machine for producing hosiery, from the Genoese their velvet, from the Venetians their mirrors, than it benefited from those who vanquished the enemies of France and took their fortresses. In the eyes of a philosopher a sovereign may deserve more praise if he has encouraged men like Le Brun, Le Sueur, and Audran, [3] if he has had the battles of Alexander painted and engraved, and the victories of our generals represented in tapestry, than he would for having gained those victories. Place on one side of the scales the actual advantages of the most sublime sciences and the most honored arts, and on the other side the advantages of the mechanical arts, and you will find that esteem has not been accorded to the one and to the other in just proportion to the benefits they bring. You will discover that far more praise has been heaped on those men who spend their time making us believe that we are happy, than on those who actually bring us happiness. How strangely we judge! We expect everyone to pass his time in a useful manner, and we disdain useful men.

 
General purpose of the arts . Man is only the minister or interpreter of nature: he can only understand or act insofar as he has knowledge of the beings that surround him, either by means of experiment or reflection. His bare hand can only achieve a small number of effects, however robust, tireless, and supple it may be; it succeeds in great enterprises only with the help of instruments and rules. The same is true of the understanding. It is as if instruments and rules provided additional muscles for the arms, and additional energy for the mind. The general purpose of any art, or of any system of instruments and rules concurring toward the same end, is to impress specific forms onto the basic element provided by nature. This element can be either matter, or spirit, or some function of the soul, or some product of nature. However, I shall devote most of my attention to the mechanical arts, particularly because other authors have written little about them. In these arts man's power is limited to moving natural objects closer or farther away. Man is capable of everything or nothing, depending on whether it is or is not possible to bring objects closer or move them farther away ( see Bacon, Novum Organum ).

 
A project for a general treatise on the mechanical arts . Often we do not know the origin of a mechanical art or have only vague information on its progress. That is the natural consequence of the scorn in which those who engage in these arts have been held at all times and in every learned or warlike nation. In such a situation we must have recourse to philosophic suppositions, begin from some probable hypothesis, from some first fortuitous event, and proceed from there until we reach the point to which the art has advanced. I shall explain this by an example, and I prefer to take it from the mechanical arts, which are not so well known, rather than from the liberal arts which have been described in a thousand different ways. If the origin and progress of glassmaking or papermaking were unknown, what would a philosopher do if he intended to write the history of these arts? He would suppose that a piece of cloth had accidentally fallen into a container filled with water and had remained in it long enough to dissolve, so that when the container was emptied it was found to have in it, instead of a piece of cloth, only a kind of sediment. It would have been difficult to determine the nature of that sediment, had it not been for a few remaining filaments which indicated that the original matter of the sediment had been cloth. As far as glassmaking is concerned, he would suppose that the first solid dwellings built by men were made of baked clay or brick. Now it is impossible to burn brick in a strong fire without some part of it vitrifying, and it is in this form that glass first occurred. But how far removed this dirty greenish shard is from the pure, transparent matter used in windows, etc.! Yet this or a similar fortuitous happening is the starting point from which the philosopher will proceed to the present state of glassmaking.

 
Advantages of this method . By this procedure the progress of an art would be presented in a clearer and more instructive manner than by its true history, if that were known. The difficulties that had to be overcome to improve the art would occur in an entirely natural order, the synthetic explanation of its successive steps would render it comprehensible even for very average minds, and this would divert artists onto the path leading to perfection.

 
The order that would have to be followed in such a treatise . As for the order that would have to be followed in such a treatise, I believe that it would be most advantageous to link the arts to the products of nature. An exact enumeration of these products would give rise to many arts that are as yet unknown. A detailed examination of the different aspects from which the same product can be studied would lead to the discovery of still other arts. The first of these possibilities demands a very extensive knowledge of natural history and the second, great dialectical ability. Consequently, a treatise on the arts, as I envisage it, cannot be the work of an ordinary man. Let no one imagine that I am engaged in idle speculation and that the discoveries I promise are mere figments of my imagination. I have already pointed out that the history of nature is incomplete without the history of the arts, and here I echo a philosopher [Bacon] whom I never tire of praising because I never tire of reading him. I have already suggested to the naturalists that they perfect their studies of the vegetable, mineral, and animal kingdoms by including the experiments of the mechanical arts, a branch of knowledge much more important for true philosophy. Now I shall dare to add with him: Ergo rem quam ago, non opinionem, sed opus esse; eamque non sectae alicujus, aut placiti, sed utilitatis esse et amplitudinis immensae fundamenta . [4] We are not dealing here with a philosophical system nor with the whims of one man, but with the decrees of experience and of reason and the foundation of an immense edifice. Whoever thinks otherwise seeks to limit the sphere of our knowledge and to discourage men's minds. We owe to chance very important discoveries we did not actively seek. Should we assume that we will not find anything if we add our efforts to the whims of chance and introduce order and method into our research? If we now possess secrets that men formerly did not hope to uncover, and if we may conjecture from the experience of the past, why should the future not hold riches for us that we can scarcely count on today? If, a few centuries ago, anyone had said to those people who measure possibilities by the reach of their genius and who do not imagine anything beyond what they already know, that there exists a dust that breaks rocks and overthrows the thickest walls from an unbelievable distance, that a few pounds of this dust, enclosed in the depths of the earth, shake the earth, make their way through the enormous mass that covers them, and open up an abyss large enough to contain an entire city, these people would certainly have compared such effects to the action of wheels, pulleys, levers, counterweights, and other known machines; they would have declared that such a dust is a mere figment of the imagination and that only lightning, or the cause that produces earthquakes by means of an inimitable mechanism, can produce such fearful prodigies. Thus we may conclude that the great philosopher spoke to his century and to all the centuries to come. We may ask, as he would have done, how much erroneous speculation would have been occasioned by the project of raising water by fire, as was carried out for the first time in London, [5] especially if the inventor of the machine would have modestly presented himself as a man little versed in mechanics? If this were the only attitude toward inventions nothing either great or small would be produced. Men who render hasty judgments upon inventions that do not deviate from established practice and sometimes are merely slight modifications of familiar machines, requiring at most a skillful worker to carry them out, men, I repeat, who are so narrow-minded that they judge these inventions to be impossible, should know that they themselves are not learned enough to formulate appropriate aspirations. The chancellor Bacon tells them so: Qui sumpta , or what is even more inexcusable, qui neglecta ex his quae praesto sunt conjectura, ea aut impossibilia, aut minus verisimilia, putet; eum scire debere se non satis doctum, ne ad optandum quidem commode et apposite esse . [6]

 
Another reason for carrying on research . We ought also to be encouraged in our research and prompted to look attentively around us, since so many centuries have gone by without men becoming aware of important things which they had, so to speak, right before their eyes, such as the arts of printing and engraving. How strange is the condition of the human mind! During the act of discovery it mistrusts its strength, it becomes entangled in self-created difficulties and what it seeks seems impossible to find. Once the discovery is made, the mind no longer conceives why it was necessary to seek so long, and feels sorry for its inadequacy .

 
Remarkable differences between machines . Having now set forth my ideas concerning a philosophic treatise on the arts in general, I am going to continue with some useful remarks on the manner of treating certain mechanical arts individually. Sometimes we use a very complex machine to produce an effect that appears quite simple; at other times a machine that is really very simple produces by itself a very complex action. In the first case one must begin by stating the effect to be produced, since it is easily grasped and will not burden one's memory with knowledge nor confuse one's mind. The description of the machine will then follow. In the second case, on the contrary, it is more to the point to go from the description of the machine to knowledge of its effect. The effect of a clock is to divide time into equal parts with the aid of a needle that moves evenly and very slowly on a marked surface. If then I show a clock to someone who does not know this machine, I will first explain its effects and will then deal with its mechanism. I shall certainly not proceed in the same manner with someone who asks me what a stocking-stitch is, or cloth, or drugget, or velvet, or satin. Here I would begin with a detailed description of the frames on which these materials are produced. If the construction of the machine is clear, its effect is grasped all at once, something that might be impossible without this preliminary explanation. Anyone who would like to convince himself of the truth of these remarks should try to define exactly what gauze is, without presupposing any knowledge of the machine of the gauze-maker.

 
Of the geometry of the arts . Everyone will readily agree that there are few artists who can dispense with the elements of mathematics. Yet here we have a paradox, although its truth is not immediately obvious: in many situations knowledge of these elements would actually hamper an artist if, in practice, the precepts of mathematics were not corrected by an extensive knowledge of physical circumstances; such as location, position, irregular figures, materials and their qualities, elasticity, rigidity, friction, consistency, duration, as well as the effects of air, water, cold, heat, dryness, and so forth. It is clear that the elements of academic geometry constitute only the simplest and least complex elements of workshop geometry. There exists not one lever in nature that is the same as the one which Varignon presupposes in his propositions; [7] there exists not one lever in nature whose factors can all be calculated. Among these factors we find a great number, some of them very essential in practice, which cannot even be subjected to the mathematical operations by which we determine the slightest discernible differences of quantity. Hence a man who knows only theoretical geometry is usually not skillful, and an artist who knows only experimental geometry is very limited as a worker. But, in my opinion, experience shows us that it is easier for an artist to get along without theoretical geometry than for any man to get along without some experimental geometry. In spite of calculus the entire subject of friction has remained the province of experimental and practical mathematics. It is remarkable how far we can go with only this mathematics. How many bad machines are suggested every day by men who imagine that levers, wheels, pulleys, and cables perform in a machine as they do on paper! Because they have taken part in practical work, they have never learned the difference between the effects of the machine itself and of its section. We will add a second observation since the subject suggests it: there are machines that are successful on a small scale but not on a large scale. Of some others the opposite is true. I believe that the latter should include all the machines whose effect depends principally on the considerable weight of their component parts, on the force of reaction in a fluid, or on a great volume of elastic matter upon which these machines have to act. If one constructs them on a small scale, the weight of the parts is reduced to nothing, the reaction of the fluid is almost nonexistent, the forces on which one has counted disappear and the machine is ineffective. However, just as there is a point, if we may use the term, a limit that stands in relation to the size of the machine, where it ceases to be effective, there is another below or beyond which the potential of its mechanism does not produce its maximum effect. Every machine has, in the language of geometry, a maximum size. When we consider each part in relation to its most perfect functioning, it has a size that is determined by the other parts. Similarly, from the point of view of its most perfect functioning, the whole has a size determined by the machine, by its intended use, and by an infinity of other matters. But where, you will ask, is the limit in the dimensions of a machine, beyond or below which it is either too large or too small? Which is the actual and absolute size of an excellent watch, a perfect mill, or a ship of the best possible construction? To give us an approximate solution to these problems, we need the experimental and practical geometry of several centuries, assisted by the most subtle theoretical geometry, I am convinced that it is impossible to obtain any satisfactory result when these types of geometry are kept separate, and that it is very difficult to do so even when they are combined.

 
Of the language of the arts . I have found the language of the arts to be very imperfect for two reasons: the scarcity of proper nomenclature and the frequency of synonyms. Some tools have several different names while others have only the generic name "engine" or "machine," without any additional name to distinguish them. At times an insignificant difference is enough to make artists invent specific names to substitute for the generic name. At other times a tool that is distinctive because of its form and use either has no name or is given the name of another tool with which it has nothing in common. One would wish for more attention to analogy of form and use. Geometers do not have as many names as they have figures, but in the arts a hammer, a pair of tongs, a bucket, a shovel, etc., have almost as many names as there are arts. A good part of the language changes from manufacture to manufacture. Yet I am convinced that the most unusual operations and the most complex machines could be explained by a rather small number of familiar, well-known terms, if it were decided to use technical terms only when they communicate a distinctive idea. What I am saying must carry conviction for anyone who considers that complex machines are only combinations of simple machines, that there are few simple machines, and that in the description of any operation all the movements can be reduced, without any significant error, to rectilinear and circular movements. It would be desirable if a good logician, well versed in the arts, undertook to describe the elements of a "grammar of the arts." For a first step he would have to determine the value of the correlatives "big," "large," "average," "thin," "thick," "slight," "small," "light," "heavy," etc. For this purpose one must seek a constant measure in nature or evaluate the height, width, and average force of man, and relate to it all indeterminate expressions of quantity, or at the least set up tables to which artists would be asked to make their language conform. The second step would be to decide on the differences and similarities between the form and the use of one instrument and another, between one operation and another, in order to determine when these should keep the same name and when they should be given different names. I do not doubt that anyone who undertakes this task will find it necessary to eliminate synonyms rather than to introduce new terms. I am also sure that it is more difficult to give a good definition of common terms, such as "elegance" in painting, "knot" in trimming, "hollow" in several arts, than it is to explain the most complicated machines. It is the lack of precise definitions and the great number, not the diversity, of movements in various operations that makes it difficult to speak clearly about the arts. The only remedy for the second problem is to familiarize oneself with the objects: they are well worth the trouble whether we think of the advantages they bring us or of the fact that they do honor to the human mind. In what physical or metaphysical system do we find more intelligence, discernment, and consistency than in the machines for drawing gold or making stockings, and in the frames of the braid-makers, the gauzemakers, the drapers, or the silk workers? What mathematical demonstration is more complicated than the mechanism of certain clocks or the different operations to which we submit the fiber of hemp or the chrysalis of the silkworm before obtaining a thread with which we can weave? What projection is more beautiful, more subtle, and more unusual than the projection of a design onto the threads of a simple and from there onto the threads of a warp? What can conceivably be more subtle than the art of shadowing velvet? I could never enumerate all the marvels that amaze anyone who looks at factories, unless his eyes are closed by prejudice or stupidity.

I shall follow the example of the English philosopher and mention three inventions that were unknown to the ancients. It is to the shame of modern history and poetry that the names of their inventors are scarcely known. I am speaking of the art of printing, the discovery of gunpowder, and the properties of the magnetic needle. What a revolution these discoveries have brought about in the republic of letters, in military art, and in seafaring! The magnetic needle has led our ships to the most remote regions, typographic characters have created enlightened communication between learned men of all countries and all future time, and gunpowder has occasioned all the architectural masterpieces that defend our frontiers as well as those of our enemies; these three arts have almost transformed the face of the earth.

Let us finally render artists the justice that is their due. The liberal arts have sung their own praise long enough; they should now raise their voice in praise of the mechanical arts. The liberal arts must free the mechanical arts from the degradation in which these have so long been held by prejudice, while royal protection must save them from the indigent state in which they still languish. The artisans have thought they deserved disdain because they were in fact disdained; let us teach them to think better of themselves, only then can we obtain more perfect products from them! We would wish that from the halls of the academies there would emerge a man who would go into the workshops, record everything noteworthy about the arts, and set it forth in a work that would induce the artists to read, the philosophers to think usefully, and the nobles to begin exercising their authority and their munificence in a useful manner.

If we may give some advice to learned men, we would suggest that they practice what they teach, namely not to judge too hastily nor to condemn an invention as useless because in its early stages it does not bring all the advantages that could be expected of it. If Montaigne, who in other ways was so much of a philosopher, returned among us, he would blush to have written that "firearms are so little effective, except in deafening our ears—to which everyone has become accustomed" that he hopes they will drop out of use. [8] Would he not have shown greater wisdom if he had encouraged the harquebusiers of his time to replace the match and wheellock by some machine activated by gunpowder? And would he not have shown more perspicacity if he had predicted that one day such a machine would be invented? Imagine Bacon in the place of Montaigne: you would see him study the nature of the agent and prophesy, if I may say so—grenades, mines, cannons, bombs, and the entire apparatus of military pyrotechnics. However, Montaigne is not the only philosopher who decided too hastily whether a machine is possible or impossible. Descartes, that extraordinary genius who was born both to confuse and to lead men, and many others, who were certainly the equals of the author of the Essais , maintained that the mirror of Archimedes was a fiction. Yet this mirror is exhibited in the Jardin du Roi for all learned men to see. M. Buffon, who rediscovered it, is using it so successfully that we can no longer doubt the results which Archimedes is supposed to have achieved with it, on the walls of Syracuse. [9] Such great examples suffice to render us circumspect.

On the other hand we invite the artists to take counsel with learned men and not to allow their discoveries to perish with them. The artists should know that to lock up a useful secret is to render oneself guilty of theft from society. It is just as despicable to prefer the interest of one individual to the common welfare in this case as in a hundred others where the artists themselves would not hesitate to decide for the common good. If they communicate their discoveries they will be freed of several preconceptions and especially of the illusion, which almost all of them hold, that their art has reached its ultimate perfection. Because they have so little learning they are often inclined to blame the nature of things for a defect that exists only in themselves. Obstacles seem insuperable to them whenever they do not know the means of overcoming them. Let them carry out experiments and let everyone make his contribution to these experiments: the artist should contribute his work, the academician his knowledge and advice, the rich man the cost of materials, labor, and time; soon our arts and our manufactures will be as superior as we could wish to those of other countries.

 
Of the superiority of one process of manufacture over another . But the superiority of one process over another will depend primarily on the quality of the materials used, together with the speed of work and the perfection of workmanship. The quality of the materials must be assured by inspection. As for the speed of work and the perfection of workmanship, they depend only on the number of workers brought together. When a process of manufacture employs many workers, each operation will be the responsibility of a different man. A particular workman will spend his lifetime performing one single operation; hence each operation is carried out quickly and well, and moreover the best-made product is also the cheapest. It is also true that when a great number of workers are assembled, taste and workmanship necessarily improve because there will be some who are able to reflect, put facts together, and discover the only way to surpass their fellow workers: they must economize on materials, make better use of time, or excel in inventiveness. This they can do by introducing either a new machine or a more practical process. If foreign industry does not surpass our manufacture in Lyon, it is not because our processes are unknown elsewhere; everywhere we find the same looms, the same silks, and more or less the same practices, but only in Lyon are there thirty thousand workers assembled, all working on the manufacture of the same material.

We could make this article even longer, but what we have already said suffices for those readers who know how to think, and we could never write an article long enough for the others. Perhaps in some places people will find our metaphysics too daring, but that was inevitable. We had to speak of art in general and, consequently, had to deal in generalizations. Good sense tells us, however, that the more general a proposition the more abstract it is, since abstraction consists in extending a truth by eliminating from its statement terms that particularize it. If only we could have spared the reader these thorny passages, we would have spared ourselves a great deal of work.

Notes

1. [Much of this description has recently been reproduced by Charles C. Gillispie. See Bibliography, p. xl.]

2. [Diderot is here referring to Book I, Aphorism LXXXIII: "... the dignity of the human mind is lowered by long and frequent intercourse with experiments and particulars, which are the objects of sense, and confined to matter; especially since such matters generally require labor in investigation, are mean subjects for meditation, harsh in discourse, unproductive in practice, infinite in number, and delicate in their subtlety. Hence we have seen the true path not only deserted, but intercepted and blocked up, experience being rejected with disgust, and not merely neglected or improperly applied."]

3. [Charles le Brun (1619–1690) and Eustache le Sueur (1617-1655) were painters, Gérard Audran (1640–1703), an engraver who made engravings of many of their paintings.]

4. [Francis Bacon, Cogitata et Visa , in The Works of Francis Bacon , ed. James Spedding (Boston: Taggard and Tompkins, 1863), VII, 140: "Therefore I am not dealing with opinion but with actual performance, and this provides the foundations, not of any sect or school, but rather of great utility and further development."]

5. [The steam engine patented by Capt. Thomas Savery in 1698.]

6. [ Cogitata et Visa ( The Works of Francis Bacon , VII, 135). Diderot paraphrases this quotation in the preceding sentence.]

7. [Pierre Varignon (1654-1722), a famous mathematician, member of the Academy of Sciences, and author of a treatise on mechanics, Nouvelle mécanique ou statique (1725).]

8. [Michel de Montaigne, Essais , Bk. I, chap. 48, "Des Destries."]

9. [Diderot is referring to the story that Archimedes invented a burning mirror which destroyed the ships of the Romans when they besieged Syracuse. Buffon reconstructed such a mirror in 1747 in the Jardin du Roi , the botanical garden in Paris, known today as the Jardin des Plantes .]