I am happy to have been able to publish this book in the year of the 300th anniversary of the birth of Diderot. That happened however by chance, for it is the result of researches and reflections extended for more than 35 years. I am now convinced in the value of this book by Diderot, so much so that I dare to count it as one of the most important works in the Western history of aesthetics. Because of that, it is all the more surprising that there has been no monograph on this book, even in the size of article. My book is the first and the only study on the Treatise on Painting by Diderot (generally known in an inappropriate title of Essays on Paining).

I would like to mention four points, among others, that constitute its importance. The first point concerns the organic notion of nature. As Diderot adopted the definition of art as imitation of nature (up to the period of redaction of this book, he preferred calling art “arts d’imitation”), the conformation of nature is to be realized in works of art. As we know, the modern theory of art was based on the notion of organism. Before that Kant defined correctly organism (Critique of Judgment, 2nd Part), Diderot tried to characterize the structure of nature, following especially Leibniz and a notion of composition of painting shared by the theorists before him. The chapter on drawing of his Treatise can be regarded as a philosophy of nature, with this remarkable difference that he extended the field of the organic structure, from the individual being to the societal scene, so that he succeeded in explaining the whole structure of a work of art with this concept.

The second point is his notion of “tact”. The appreciation of work of art, or the judgment of taste if you prefer, is performed by tact. Diderot regards tact as the result of many past experiences that we have forgotten. In other words, tact is an aesthetic faculty that becomes, or matures, so that we experience the same work of art differently through our life. In this conception, we must remark a deep connection with the famous theory of “perception of relations” he had exposed in the article on “Beauty” (Beau) in the Encycloedie, although he does not mention this theory in the Treatise. Especially remarkable is his original notion of “accessory”, i.e., supplemental objects garnished to the main figure or object of a painting. Diderot finds in it a means of letting the ideal subject appear as the effect of the overlapping of two different objects=meanings. Tact crystalizes therefore, according to my reading, many important factors of our aesthetic experiences, such as: subconscious working of delicate sensibility, personal history accumulated in our body and the hermeneutic procedure of transcending the visual elements to the ideological level.

The third point concerns the metaphysics of beauty, i.e. the philosophical theory founding beauty. Diderot’s starting point as philosopher was a translation of Shaftesbury. While the British philosopher wished to prove, against the pessimistic view of Hobbes, the rationality of the universe referring to its beauty, which testifies the order of the world; Diderot wished, already in his translation of Shaftesbury, to rationalize (to give philosophical basis to) the artistic beauty. This attitude means the need of philosophy, i.e. aesthetics for art: art is not something self-evident for Diderot. This orientation governs all aesthetic texts of Diderot. In theTreatise, the last chapter is dedicated to this problem, where he founds beauty and goodness on truth ,i.e. the real structure of the world. In this context, I pose a question whether this triad of truth-goodness-beauty is really something established since a long time as most people believe: I have the impression that Diderot found this triad through his efforts of argument.

The last point is historical one. Diderot’s Treatise has a deep and essential relation to the establishment of the modern aesthetics as a new philosophical discipline. The form of the discourse on art changed from poetics (theory of production) to aesthetics (theory of appreciation). While the former was mainly carried out by artists, it was the philosopher, and the critics who performed the latter. As it concerns a real revolution, there naturally happened a battle between artists (old authorities) and critics/philosophers (new comers). We can know in the case of the criticism of the Salon of 1746 by La Font de Saint-Yenne, the real founder of the modern art criticism, how vehement was the reaction shown by artists. Diderot joined to this new field about ten years later. As a beginner, he felt indispensable to learn from professional artists about art, and he got such great masters as teacher as Chardin, Quentin La Tour, Falconet, among many others. But he believed he had something to teach them as well. The above mentioned structure of nature is such a property of philosopher, but essentially philosopher is unrivalled in the part of idea of art: in fact Diderot gave some painters and sculptors ideas of composition of work. Ideas belong to philosopher, and technique to artists. At the just moment when he was going to write the Treatise, Diderot was engaged in a dispute through correspondence with Falconet on the value of the reputation in the posterity (their letters are gathered in a volume as Le Pour et le contre). Their real problem in fact concerned the reliability of the judgment given by the ancient writers on the artworks that became legendary master pieces thanks to the authority acknowledged to these writers. Falconet believes only in what he witnesses with his own eyes. Diderot makes efforts to persuade the sculptor the value of the discourses of Pliny or Pausanias, because it concerns in the final account the value of the critical text of himself. Artist has also a dilemma: in order to attain the prestige of high culture, he has absolutely to emphasize the ideal side of his art.

It was a real battle between artist and philosopher concerning the right of discourse on art. Diderot lived this drama, and no other aesthetic texts from this period reflects this real aspect of history than his Treatise on Painting. It is not a fact outside of the theory or the text, for the tension between the painting of history (the side of the idea) and the still life (the side of the technique) dominates the whole text of his Treatise.

My Study is divided into three parts. After the Introduction describing the relation between Diderot and artists, its main and first part consists in the detailed commentary of the text: I obliged myself to focus on every word or phrase that seems even slightly obscure. The part two is dedicated to reflections on the Treatise and aesthetics of Diderot. It goes without saying that its core is the interpretation of theory developed in theTreatise, of which the outline of the result is shown in the above description of the work. Besides, this part contains a general survey of the philosophical work of Diderot; an outline of the development of his aesthetic thought from the translation of Shaftesbury to the Treatise; a study on the different forms of the texts of Diderot; and a study on his style of work, which is reflected on the conformation of his text. In addition, I add an appendix on aesthetics of Goethe and Diderot, based on the commentary of Goethe on the Treatise.

The part three present the text of the Treatise in bilingual form. I revised the text. I investigated the original form of the text at Stockholm and Moscow and autographs of Diderot at Paris and Vienna.

Ken-ichi Sasaki